diff options
author | Lars-Peter Clausen <lars@metafoo.de> | 2014-02-17 14:10:00 (GMT) |
---|---|---|
committer | Jonathan Cameron <jic23@kernel.org> | 2014-03-01 21:04:29 (GMT) |
commit | bdc8cda1d010887c06bd8c29564b74cd61ec0a7b (patch) | |
tree | a0c6dc8b18b450d23578b4872b421c6702a335a3 /drivers/iio | |
parent | 588858c4df831226fa366aed295a426b07a417e1 (diff) | |
download | linux-bdc8cda1d010887c06bd8c29564b74cd61ec0a7b.tar.xz |
iio:adc: Add Xilinx XADC driver
The Xilinx XADC is a ADC that can be found in the series 7 FPGAs from Xilinx.
The XADC has a DRP interface for communication. Currently two different
frontends for the DRP interface exist. One that is only available on the ZYNQ
family as a hardmacro in the SoC portion of the ZYNQ. The other one is available
on all series 7 platforms and is a softmacro with a AXI interface. This driver
supports both interfaces and internally has a small abstraction layer that hides
the specifics of these interfaces from the main driver logic.
The ADC has a couple of internal channels which are used for voltage and
temperature monitoring of the FPGA as well as one primary and up to 16 channels
auxiliary channels for measuring external voltages. The external auxiliary
channels can either be directly connected each to one physical pin on the FPGA
or they can make use of an external multiplexer which is responsible for
multiplexing the external signals onto one pair of physical pins.
The voltage and temperature monitoring channels also have an event capability
which allows to generate a interrupt when their value falls below or raises
above a set threshold.
Buffered sampling mode is supported by the driver, but only for AXI-XADC since
the ZYNQ XADC interface does not have capabilities for supporting buffer mode
(no end-of-conversion interrupt). If buffered mode is supported the driver will
register two triggers. One "xadc-samplerate" trigger which will generate samples
with the configured samplerate. And one "xadc-convst" trigger which will
generate one sample each time the CONVST (conversion start) signal is asserted.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers/iio')
-rw-r--r-- | drivers/iio/adc/Kconfig | 13 | ||||
-rw-r--r-- | drivers/iio/adc/Makefile | 2 | ||||
-rw-r--r-- | drivers/iio/adc/xilinx-xadc-core.c | 1333 | ||||
-rw-r--r-- | drivers/iio/adc/xilinx-xadc-events.c | 254 | ||||
-rw-r--r-- | drivers/iio/adc/xilinx-xadc.h | 209 |
5 files changed, 1811 insertions, 0 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index c02c4fb..5553206 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -214,4 +214,17 @@ config VIPERBOARD_ADC Say yes here to access the ADC part of the Nano River Technologies Viperboard. +config XILINX_XADC + tristate "Xilinx XADC driver" + depends on ARCH_ZYNQ || MICROBLAZE || COMPILE_TEST + depends on HAS_IOMEM + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Say yes here to have support for the Xilinx XADC. The driver does support + both the ZYNQ interface to the XADC as well as the AXI-XADC interface. + + The driver can also be build as a module. If so, the module will be called + xilinx-xadc. + endmenu diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 6d96b0f..89f1216 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -23,3 +23,5 @@ obj-$(CONFIG_TI_AM335X_ADC) += ti_am335x_adc.o obj-$(CONFIG_TWL6030_GPADC) += twl6030-gpadc.o obj-$(CONFIG_VF610_ADC) += vf610_adc.o obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o +xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o +obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o diff --git a/drivers/iio/adc/xilinx-xadc-core.c b/drivers/iio/adc/xilinx-xadc-core.c new file mode 100644 index 0000000..ab52be2 --- /dev/null +++ b/drivers/iio/adc/xilinx-xadc-core.c @@ -0,0 +1,1333 @@ +/* + * Xilinx XADC driver + * + * Copyright 2013-2014 Analog Devices Inc. + * Author: Lars-Peter Clauen <lars@metafoo.de> + * + * Licensed under the GPL-2. + * + * Documentation for the parts can be found at: + * - XADC hardmacro: Xilinx UG480 + * - ZYNQ XADC interface: Xilinx UG585 + * - AXI XADC interface: Xilinx PG019 + */ + +#include <linux/clk.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/sysfs.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/events.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/trigger.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#include "xilinx-xadc.h" + +static const unsigned int XADC_ZYNQ_UNMASK_TIMEOUT = 500; + +/* ZYNQ register definitions */ +#define XADC_ZYNQ_REG_CFG 0x00 +#define XADC_ZYNQ_REG_INTSTS 0x04 +#define XADC_ZYNQ_REG_INTMSK 0x08 +#define XADC_ZYNQ_REG_STATUS 0x0c +#define XADC_ZYNQ_REG_CFIFO 0x10 +#define XADC_ZYNQ_REG_DFIFO 0x14 +#define XADC_ZYNQ_REG_CTL 0x18 + +#define XADC_ZYNQ_CFG_ENABLE BIT(31) +#define XADC_ZYNQ_CFG_CFIFOTH_MASK (0xf << 20) +#define XADC_ZYNQ_CFG_CFIFOTH_OFFSET 20 +#define XADC_ZYNQ_CFG_DFIFOTH_MASK (0xf << 16) +#define XADC_ZYNQ_CFG_DFIFOTH_OFFSET 16 +#define XADC_ZYNQ_CFG_WEDGE BIT(13) +#define XADC_ZYNQ_CFG_REDGE BIT(12) +#define XADC_ZYNQ_CFG_TCKRATE_MASK (0x3 << 8) +#define XADC_ZYNQ_CFG_TCKRATE_DIV2 (0x0 << 8) +#define XADC_ZYNQ_CFG_TCKRATE_DIV4 (0x1 << 8) +#define XADC_ZYNQ_CFG_TCKRATE_DIV8 (0x2 << 8) +#define XADC_ZYNQ_CFG_TCKRATE_DIV16 (0x3 << 8) +#define XADC_ZYNQ_CFG_IGAP_MASK 0x1f +#define XADC_ZYNQ_CFG_IGAP(x) (x) + +#define XADC_ZYNQ_INT_CFIFO_LTH BIT(9) +#define XADC_ZYNQ_INT_DFIFO_GTH BIT(8) +#define XADC_ZYNQ_INT_ALARM_MASK 0xff +#define XADC_ZYNQ_INT_ALARM_OFFSET 0 + +#define XADC_ZYNQ_STATUS_CFIFO_LVL_MASK (0xf << 16) +#define XADC_ZYNQ_STATUS_CFIFO_LVL_OFFSET 16 +#define XADC_ZYNQ_STATUS_DFIFO_LVL_MASK (0xf << 12) +#define XADC_ZYNQ_STATUS_DFIFO_LVL_OFFSET 12 +#define XADC_ZYNQ_STATUS_CFIFOF BIT(11) +#define XADC_ZYNQ_STATUS_CFIFOE BIT(10) +#define XADC_ZYNQ_STATUS_DFIFOF BIT(9) +#define XADC_ZYNQ_STATUS_DFIFOE BIT(8) +#define XADC_ZYNQ_STATUS_OT BIT(7) +#define XADC_ZYNQ_STATUS_ALM(x) BIT(x) + +#define XADC_ZYNQ_CTL_RESET BIT(4) + +#define XADC_ZYNQ_CMD_NOP 0x00 +#define XADC_ZYNQ_CMD_READ 0x01 +#define XADC_ZYNQ_CMD_WRITE 0x02 + +#define XADC_ZYNQ_CMD(cmd, addr, data) (((cmd) << 26) | ((addr) << 16) | (data)) + +/* AXI register definitions */ +#define XADC_AXI_REG_RESET 0x00 +#define XADC_AXI_REG_STATUS 0x04 +#define XADC_AXI_REG_ALARM_STATUS 0x08 +#define XADC_AXI_REG_CONVST 0x0c +#define XADC_AXI_REG_XADC_RESET 0x10 +#define XADC_AXI_REG_GIER 0x5c +#define XADC_AXI_REG_IPISR 0x60 +#define XADC_AXI_REG_IPIER 0x68 +#define XADC_AXI_ADC_REG_OFFSET 0x200 + +#define XADC_AXI_RESET_MAGIC 0xa +#define XADC_AXI_GIER_ENABLE BIT(31) + +#define XADC_AXI_INT_EOS BIT(4) +#define XADC_AXI_INT_ALARM_MASK 0x3c0f + +#define XADC_FLAGS_BUFFERED BIT(0) + +static void xadc_write_reg(struct xadc *xadc, unsigned int reg, + uint32_t val) +{ + writel(val, xadc->base + reg); +} + +static void xadc_read_reg(struct xadc *xadc, unsigned int reg, + uint32_t *val) +{ + *val = readl(xadc->base + reg); +} + +/* + * The ZYNQ interface uses two asynchronous FIFOs for communication with the + * XADC. Reads and writes to the XADC register are performed by submitting a + * request to the command FIFO (CFIFO), once the request has been completed the + * result can be read from the data FIFO (DFIFO). The method currently used in + * this driver is to submit the request for a read/write operation, then go to + * sleep and wait for an interrupt that signals that a response is available in + * the data FIFO. + */ + +static void xadc_zynq_write_fifo(struct xadc *xadc, uint32_t *cmd, + unsigned int n) +{ + unsigned int i; + + for (i = 0; i < n; i++) + xadc_write_reg(xadc, XADC_ZYNQ_REG_CFIFO, cmd[i]); +} + +static void xadc_zynq_drain_fifo(struct xadc *xadc) +{ + uint32_t status, tmp; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status); + + while (!(status & XADC_ZYNQ_STATUS_DFIFOE)) { + xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp); + xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &status); + } +} + +static void xadc_zynq_update_intmsk(struct xadc *xadc, unsigned int mask, + unsigned int val) +{ + xadc->zynq_intmask &= ~mask; + xadc->zynq_intmask |= val; + + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, + xadc->zynq_intmask | xadc->zynq_masked_alarm); +} + +static int xadc_zynq_write_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t val) +{ + uint32_t cmd[1]; + uint32_t tmp; + int ret; + + spin_lock_irq(&xadc->lock); + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, + XADC_ZYNQ_INT_DFIFO_GTH); + + reinit_completion(&xadc->completion); + + cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_WRITE, reg, val); + xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd)); + xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp); + tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK; + tmp |= 0 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET; + xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp); + + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0); + spin_unlock_irq(&xadc->lock); + + ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ); + if (ret == 0) + ret = -EIO; + else + ret = 0; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &tmp); + + return ret; +} + +static int xadc_zynq_read_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t *val) +{ + uint32_t cmd[2]; + uint32_t resp, tmp; + int ret; + + cmd[0] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_READ, reg, 0); + cmd[1] = XADC_ZYNQ_CMD(XADC_ZYNQ_CMD_NOP, 0, 0); + + spin_lock_irq(&xadc->lock); + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, + XADC_ZYNQ_INT_DFIFO_GTH); + xadc_zynq_drain_fifo(xadc); + reinit_completion(&xadc->completion); + + xadc_zynq_write_fifo(xadc, cmd, ARRAY_SIZE(cmd)); + xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &tmp); + tmp &= ~XADC_ZYNQ_CFG_DFIFOTH_MASK; + tmp |= 1 << XADC_ZYNQ_CFG_DFIFOTH_OFFSET; + xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, tmp); + + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, 0); + spin_unlock_irq(&xadc->lock); + ret = wait_for_completion_interruptible_timeout(&xadc->completion, HZ); + if (ret == 0) + ret = -EIO; + if (ret < 0) + return ret; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp); + xadc_read_reg(xadc, XADC_ZYNQ_REG_DFIFO, &resp); + + *val = resp & 0xffff; + + return 0; +} + +static unsigned int xadc_zynq_transform_alarm(unsigned int alarm) +{ + return ((alarm & 0x80) >> 4) | + ((alarm & 0x78) << 1) | + (alarm & 0x07); +} + +/* + * The ZYNQ threshold interrupts are level sensitive. Since we can't make the + * threshold condition go way from within the interrupt handler, this means as + * soon as a threshold condition is present we would enter the interrupt handler + * again and again. To work around this we mask all active thresholds interrupts + * in the interrupt handler and start a timer. In this timer we poll the + * interrupt status and only if the interrupt is inactive we unmask it again. + */ +static void xadc_zynq_unmask_worker(struct work_struct *work) +{ + struct xadc *xadc = container_of(work, struct xadc, zynq_unmask_work.work); + unsigned int misc_sts, unmask; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_STATUS, &misc_sts); + + misc_sts &= XADC_ZYNQ_INT_ALARM_MASK; + + spin_lock_irq(&xadc->lock); + + /* Clear those bits which are not active anymore */ + unmask = (xadc->zynq_masked_alarm ^ misc_sts) & xadc->zynq_masked_alarm; + xadc->zynq_masked_alarm &= misc_sts; + + /* Also clear those which are masked out anyway */ + xadc->zynq_masked_alarm &= ~xadc->zynq_intmask; + + /* Clear the interrupts before we unmask them */ + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, unmask); + + xadc_zynq_update_intmsk(xadc, 0, 0); + + spin_unlock_irq(&xadc->lock); + + /* if still pending some alarm re-trigger the timer */ + if (xadc->zynq_masked_alarm) { + schedule_delayed_work(&xadc->zynq_unmask_work, + msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT)); + } +} + +static irqreturn_t xadc_zynq_threaded_interrupt_handler(int irq, void *devid) +{ + struct iio_dev *indio_dev = devid; + struct xadc *xadc = iio_priv(indio_dev); + unsigned int alarm; + + spin_lock_irq(&xadc->lock); + alarm = xadc->zynq_alarm; + xadc->zynq_alarm = 0; + spin_unlock_irq(&xadc->lock); + + xadc_handle_events(indio_dev, xadc_zynq_transform_alarm(alarm)); + + /* unmask the required interrupts in timer. */ + schedule_delayed_work(&xadc->zynq_unmask_work, + msecs_to_jiffies(XADC_ZYNQ_UNMASK_TIMEOUT)); + + return IRQ_HANDLED; +} + +static irqreturn_t xadc_zynq_interrupt_handler(int irq, void *devid) +{ + struct iio_dev *indio_dev = devid; + struct xadc *xadc = iio_priv(indio_dev); + irqreturn_t ret = IRQ_HANDLED; + uint32_t status; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status); + + status &= ~(xadc->zynq_intmask | xadc->zynq_masked_alarm); + + if (!status) + return IRQ_NONE; + + spin_lock(&xadc->lock); + + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status); + + if (status & XADC_ZYNQ_INT_DFIFO_GTH) { + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_DFIFO_GTH, + XADC_ZYNQ_INT_DFIFO_GTH); + complete(&xadc->completion); + } + + status &= XADC_ZYNQ_INT_ALARM_MASK; + if (status) { + xadc->zynq_alarm |= status; + xadc->zynq_masked_alarm |= status; + /* + * mask the current event interrupt, + * unmask it when the interrupt is no more active. + */ + xadc_zynq_update_intmsk(xadc, 0, 0); + ret = IRQ_WAKE_THREAD; + } + spin_unlock(&xadc->lock); + + return ret; +} + +#define XADC_ZYNQ_TCK_RATE_MAX 50000000 +#define XADC_ZYNQ_IGAP_DEFAULT 20 + +static int xadc_zynq_setup(struct platform_device *pdev, + struct iio_dev *indio_dev, int irq) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned long pcap_rate; + unsigned int tck_div; + unsigned int div; + unsigned int igap; + unsigned int tck_rate; + + /* TODO: Figure out how to make igap and tck_rate configurable */ + igap = XADC_ZYNQ_IGAP_DEFAULT; + tck_rate = XADC_ZYNQ_TCK_RATE_MAX; + + xadc->zynq_intmask = ~0; + + pcap_rate = clk_get_rate(xadc->clk); + + if (tck_rate > XADC_ZYNQ_TCK_RATE_MAX) + tck_rate = XADC_ZYNQ_TCK_RATE_MAX; + if (tck_rate > pcap_rate / 2) { + div = 2; + } else { + div = pcap_rate / tck_rate; + if (pcap_rate / div > XADC_ZYNQ_TCK_RATE_MAX) + div++; + } + + if (div <= 3) + tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV2; + else if (div <= 7) + tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV4; + else if (div <= 15) + tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV8; + else + tck_div = XADC_ZYNQ_CFG_TCKRATE_DIV16; + + xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, XADC_ZYNQ_CTL_RESET); + xadc_write_reg(xadc, XADC_ZYNQ_REG_CTL, 0); + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, ~0); + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTMSK, xadc->zynq_intmask); + xadc_write_reg(xadc, XADC_ZYNQ_REG_CFG, XADC_ZYNQ_CFG_ENABLE | + XADC_ZYNQ_CFG_REDGE | XADC_ZYNQ_CFG_WEDGE | + tck_div | XADC_ZYNQ_CFG_IGAP(igap)); + + return 0; +} + +static unsigned long xadc_zynq_get_dclk_rate(struct xadc *xadc) +{ + unsigned int div; + uint32_t val; + + xadc_read_reg(xadc, XADC_ZYNQ_REG_CFG, &val); + + switch (val & XADC_ZYNQ_CFG_TCKRATE_MASK) { + case XADC_ZYNQ_CFG_TCKRATE_DIV4: + div = 4; + break; + case XADC_ZYNQ_CFG_TCKRATE_DIV8: + div = 8; + break; + case XADC_ZYNQ_CFG_TCKRATE_DIV16: + div = 16; + break; + default: + div = 2; + break; + } + + return clk_get_rate(xadc->clk) / div; +} + +static void xadc_zynq_update_alarm(struct xadc *xadc, unsigned int alarm) +{ + unsigned long flags; + uint32_t status; + + /* Move OT to bit 7 */ + alarm = ((alarm & 0x08) << 4) | ((alarm & 0xf0) >> 1) | (alarm & 0x07); + + spin_lock_irqsave(&xadc->lock, flags); + + /* Clear previous interrupts if any. */ + xadc_read_reg(xadc, XADC_ZYNQ_REG_INTSTS, &status); + xadc_write_reg(xadc, XADC_ZYNQ_REG_INTSTS, status & alarm); + + xadc_zynq_update_intmsk(xadc, XADC_ZYNQ_INT_ALARM_MASK, + ~alarm & XADC_ZYNQ_INT_ALARM_MASK); + + spin_unlock_irqrestore(&xadc->lock, flags); +} + +static const struct xadc_ops xadc_zynq_ops = { + .read = xadc_zynq_read_adc_reg, + .write = xadc_zynq_write_adc_reg, + .setup = xadc_zynq_setup, + .get_dclk_rate = xadc_zynq_get_dclk_rate, + .interrupt_handler = xadc_zynq_interrupt_handler, + .threaded_interrupt_handler = xadc_zynq_threaded_interrupt_handler, + .update_alarm = xadc_zynq_update_alarm, +}; + +static int xadc_axi_read_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t *val) +{ + uint32_t val32; + + xadc_read_reg(xadc, XADC_AXI_ADC_REG_OFFSET + reg * 4, &val32); + *val = val32 & 0xffff; + + return 0; +} + +static int xadc_axi_write_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t val) +{ + xadc_write_reg(xadc, XADC_AXI_ADC_REG_OFFSET + reg * 4, val); + + return 0; +} + +static int xadc_axi_setup(struct platform_device *pdev, + struct iio_dev *indio_dev, int irq) +{ + struct xadc *xadc = iio_priv(indio_dev); + + xadc_write_reg(xadc, XADC_AXI_REG_RESET, XADC_AXI_RESET_MAGIC); + xadc_write_reg(xadc, XADC_AXI_REG_GIER, XADC_AXI_GIER_ENABLE); + + return 0; +} + +static irqreturn_t xadc_axi_interrupt_handler(int irq, void *devid) +{ + struct iio_dev *indio_dev = devid; + struct xadc *xadc = iio_priv(indio_dev); + uint32_t status, mask; + unsigned int events; + + xadc_read_reg(xadc, XADC_AXI_REG_IPISR, &status); + xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &mask); + status &= mask; + + if (!status) + return IRQ_NONE; + + if ((status & XADC_AXI_INT_EOS) && xadc->trigger) + iio_trigger_poll(xadc->trigger, 0); + + if (status & XADC_AXI_INT_ALARM_MASK) { + /* + * The order of the bits in the AXI-XADC status register does + * not match the order of the bits in the XADC alarm enable + * register. xadc_handle_events() expects the events to be in + * the same order as the XADC alarm enable register. + */ + events = (status & 0x000e) >> 1; + events |= (status & 0x0001) << 3; + events |= (status & 0x3c00) >> 6; + xadc_handle_events(indio_dev, events); + } + + xadc_write_reg(xadc, XADC_AXI_REG_IPISR, status); + + return IRQ_HANDLED; +} + +static void xadc_axi_update_alarm(struct xadc *xadc, unsigned int alarm) +{ + uint32_t val; + unsigned long flags; + + /* + * The order of the bits in the AXI-XADC status register does not match + * the order of the bits in the XADC alarm enable register. We get + * passed the alarm mask in the same order as in the XADC alarm enable + * register. + */ + alarm = ((alarm & 0x07) << 1) | ((alarm & 0x08) >> 3) | + ((alarm & 0xf0) << 6); + + spin_lock_irqsave(&xadc->lock, flags); + xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); + val &= ~XADC_AXI_INT_ALARM_MASK; + val |= alarm; + xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val); + spin_unlock_irqrestore(&xadc->lock, flags); +} + +static unsigned long xadc_axi_get_dclk(struct xadc *xadc) +{ + return clk_get_rate(xadc->clk); +} + +static const struct xadc_ops xadc_axi_ops = { + .read = xadc_axi_read_adc_reg, + .write = xadc_axi_write_adc_reg, + .setup = xadc_axi_setup, + .get_dclk_rate = xadc_axi_get_dclk, + .update_alarm = xadc_axi_update_alarm, + .interrupt_handler = xadc_axi_interrupt_handler, + .flags = XADC_FLAGS_BUFFERED, +}; + +static int _xadc_update_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t mask, uint16_t val) +{ + uint16_t tmp; + int ret; + + ret = _xadc_read_adc_reg(xadc, reg, &tmp); + if (ret) + return ret; + + return _xadc_write_adc_reg(xadc, reg, (tmp & ~mask) | val); +} + +static int xadc_update_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t mask, uint16_t val) +{ + int ret; + + mutex_lock(&xadc->mutex); + ret = _xadc_update_adc_reg(xadc, reg, mask, val); + mutex_unlock(&xadc->mutex); + + return ret; +} + +static unsigned long xadc_get_dclk_rate(struct xadc *xadc) +{ + return xadc->ops->get_dclk_rate(xadc); +} + +static int xadc_update_scan_mode(struct iio_dev *indio_dev, + const unsigned long *mask) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned int n; + + n = bitmap_weight(mask, indio_dev->masklength); + + kfree(xadc->data); + xadc->data = kcalloc(n, sizeof(*xadc->data), GFP_KERNEL); + if (!xadc->data) + return -ENOMEM; + + return 0; +} + +static unsigned int xadc_scan_index_to_channel(unsigned int scan_index) +{ + switch (scan_index) { + case 5: + return XADC_REG_VCCPINT; + case 6: + return XADC_REG_VCCPAUX; + case 7: + return XADC_REG_VCCO_DDR; + case 8: + return XADC_REG_TEMP; + case 9: + return XADC_REG_VCCINT; + case 10: + return XADC_REG_VCCAUX; + case 11: + return XADC_REG_VPVN; + case 12: + return XADC_REG_VREFP; + case 13: + return XADC_REG_VREFN; + case 14: + return XADC_REG_VCCBRAM; + default: + return XADC_REG_VAUX(scan_index - 16); + } +} + +static irqreturn_t xadc_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct xadc *xadc = iio_priv(indio_dev); + unsigned int chan; + int i, j; + + if (!xadc->data) + goto out; + + j = 0; + for_each_set_bit(i, indio_dev->active_scan_mask, + indio_dev->masklength) { + chan = xadc_scan_index_to_channel(i); + xadc_read_adc_reg(xadc, chan, &xadc->data[j]); + j++; + } + + iio_push_to_buffers(indio_dev, xadc->data); + +out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int xadc_trigger_set_state(struct iio_trigger *trigger, bool state) +{ + struct xadc *xadc = iio_trigger_get_drvdata(trigger); + unsigned long flags; + unsigned int convst; + unsigned int val; + int ret = 0; + + mutex_lock(&xadc->mutex); + + if (state) { + /* Only one of the two triggers can be active at the a time. */ + if (xadc->trigger != NULL) { + ret = -EBUSY; + goto err_out; + } else { + xadc->trigger = trigger; + if (trigger == xadc->convst_trigger) + convst = XADC_CONF0_EC; + else + convst = 0; + } + ret = _xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF0_EC, + convst); + if (ret) + goto err_out; + } else { + xadc->trigger = NULL; + } + + spin_lock_irqsave(&xadc->lock, flags); + xadc_read_reg(xadc, XADC_AXI_REG_IPIER, &val); + xadc_write_reg(xadc, XADC_AXI_REG_IPISR, val & XADC_AXI_INT_EOS); + if (state) + val |= XADC_AXI_INT_EOS; + else + val &= ~XADC_AXI_INT_EOS; + xadc_write_reg(xadc, XADC_AXI_REG_IPIER, val); + spin_unlock_irqrestore(&xadc->lock, flags); + +err_out: + mutex_unlock(&xadc->mutex); + + return ret; +} + +static const struct iio_trigger_ops xadc_trigger_ops = { + .owner = THIS_MODULE, + .set_trigger_state = &xadc_trigger_set_state, +}; + +static struct iio_trigger *xadc_alloc_trigger(struct iio_dev *indio_dev, + const char *name) +{ + struct iio_trigger *trig; + int ret; + + trig = iio_trigger_alloc("%s%d-%s", indio_dev->name, + indio_dev->id, name); + if (trig == NULL) + return ERR_PTR(-ENOMEM); + + trig->dev.parent = indio_dev->dev.parent; + trig->ops = &xadc_trigger_ops; + iio_trigger_set_drvdata(trig, iio_priv(indio_dev)); + + ret = iio_trigger_register(trig); + if (ret) + goto error_free_trig; + + return trig; + +error_free_trig: + iio_trigger_free(trig); + return ERR_PTR(ret); +} + +static int xadc_power_adc_b(struct xadc *xadc, unsigned int seq_mode) +{ + uint16_t val; + + switch (seq_mode) { + case XADC_CONF1_SEQ_SIMULTANEOUS: + case XADC_CONF1_SEQ_INDEPENDENT: + val = XADC_CONF2_PD_ADC_B; + break; + default: + val = 0; + break; + } + + return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_PD_MASK, + val); +} + +static int xadc_get_seq_mode(struct xadc *xadc, unsigned long scan_mode) +{ + unsigned int aux_scan_mode = scan_mode >> 16; + + if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_DUAL) + return XADC_CONF1_SEQ_SIMULTANEOUS; + + if ((aux_scan_mode & 0xff00) == 0 || + (aux_scan_mode & 0x00ff) == 0) + return XADC_CONF1_SEQ_CONTINUOUS; + + return XADC_CONF1_SEQ_SIMULTANEOUS; +} + +static int xadc_postdisable(struct iio_dev *indio_dev) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned long scan_mask; + int ret; + int i; + + scan_mask = 1; /* Run calibration as part of the sequence */ + for (i = 0; i < indio_dev->num_channels; i++) + scan_mask |= BIT(indio_dev->channels[i].scan_index); + + /* Enable all channels and calibration */ + ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff); + if (ret) + return ret; + + ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16); + if (ret) + return ret; + + ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, + XADC_CONF1_SEQ_CONTINUOUS); + if (ret) + return ret; + + return xadc_power_adc_b(xadc, XADC_CONF1_SEQ_CONTINUOUS); +} + +static int xadc_preenable(struct iio_dev *indio_dev) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned long scan_mask; + int seq_mode; + int ret; + + ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, + XADC_CONF1_SEQ_DEFAULT); + if (ret) + goto err; + + scan_mask = *indio_dev->active_scan_mask; + seq_mode = xadc_get_seq_mode(xadc, scan_mask); + + ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(0), scan_mask & 0xffff); + if (ret) + goto err; + + ret = xadc_write_adc_reg(xadc, XADC_REG_SEQ(1), scan_mask >> 16); + if (ret) + goto err; + + ret = xadc_power_adc_b(xadc, seq_mode); + if (ret) + goto err; + + ret = xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_SEQ_MASK, + seq_mode); + if (ret) + goto err; + + return 0; +err: + xadc_postdisable(indio_dev); + return ret; +} + +static struct iio_buffer_setup_ops xadc_buffer_ops = { + .preenable = &xadc_preenable, + .postenable = &iio_triggered_buffer_postenable, + .predisable = &iio_triggered_buffer_predisable, + .postdisable = &xadc_postdisable, +}; + +static int xadc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, long info) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned int div; + uint16_t val16; + int ret; + + switch (info) { + case IIO_CHAN_INFO_RAW: + if (iio_buffer_enabled(indio_dev)) + return -EBUSY; + ret = xadc_read_adc_reg(xadc, chan->address, &val16); + if (ret < 0) + return ret; + + val16 >>= 4; + if (chan->scan_type.sign == 'u') + *val = val16; + else + *val = sign_extend32(val16, 11); + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_VOLTAGE: + /* V = (val * 3.0) / 4096 */ + switch (chan->address) { + case XADC_REG_VCCINT: + case XADC_REG_VCCAUX: + case XADC_REG_VCCBRAM: + case XADC_REG_VCCPINT: + case XADC_REG_VCCPAUX: + case XADC_REG_VCCO_DDR: + *val = 3000; + break; + default: + *val = 1000; + break; + } + *val2 = 12; + return IIO_VAL_FRACTIONAL_LOG2; + case IIO_TEMP: + /* Temp in C = (val * 503.975) / 4096 - 273.15 */ + *val = 503975; + *val2 = 12; + return IIO_VAL_FRACTIONAL_LOG2; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_OFFSET: + /* Only the temperature channel has an offset */ + *val = -((273150 << 12) / 503975); + return IIO_VAL_INT; + case IIO_CHAN_INFO_SAMP_FREQ: + ret = xadc_read_adc_reg(xadc, XADC_REG_CONF2, &val16); + if (ret) + return ret; + + div = (val16 & XADC_CONF2_DIV_MASK) >> XADC_CONF2_DIV_OFFSET; + if (div < 2) + div = 2; + + *val = xadc_get_dclk_rate(xadc) / div / 26; + + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int xadc_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, int val2, long info) +{ + struct xadc *xadc = iio_priv(indio_dev); + unsigned long clk_rate = xadc_get_dclk_rate(xadc); + unsigned int div; + + if (info != IIO_CHAN_INFO_SAMP_FREQ) + return -EINVAL; + + if (val <= 0) + return -EINVAL; + + /* Max. 150 kSPS */ + if (val > 150000) + val = 150000; + + val *= 26; + + /* Min 1MHz */ + if (val < 1000000) + val = 1000000; + + /* + * We want to round down, but only if we do not exceed the 150 kSPS + * limit. + */ + div = clk_rate / val; + if (clk_rate / div / 26 > 150000) + div++; + if (div < 2) + div = 2; + else if (div > 0xff) + div = 0xff; + + return xadc_update_adc_reg(xadc, XADC_REG_CONF2, XADC_CONF2_DIV_MASK, + div << XADC_CONF2_DIV_OFFSET); +} + +static const struct iio_event_spec xadc_temp_events[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_ENABLE) | + BIT(IIO_EV_INFO_VALUE) | + BIT(IIO_EV_INFO_HYSTERESIS), + }, +}; + +/* Separate values for upper and lower thresholds, but only a shared enabled */ +static const struct iio_event_spec xadc_voltage_events[] = { + { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_RISING, + .mask_separate = BIT(IIO_EV_INFO_VALUE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_FALLING, + .mask_separate = BIT(IIO_EV_INFO_VALUE), + }, { + .type = IIO_EV_TYPE_THRESH, + .dir = IIO_EV_DIR_EITHER, + .mask_separate = BIT(IIO_EV_INFO_ENABLE), + }, +}; + +#define XADC_CHAN_TEMP(_chan, _scan_index, _addr) { \ + .type = IIO_TEMP, \ + .indexed = 1, \ + .channel = (_chan), \ + .address = (_addr), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_OFFSET), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .event_spec = xadc_temp_events, \ + .num_event_specs = ARRAY_SIZE(xadc_temp_events), \ + .scan_index = (_scan_index), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + .shift = 4, \ + .endianness = IIO_CPU, \ + }, \ +} + +#define XADC_CHAN_VOLTAGE(_chan, _scan_index, _addr, _ext, _alarm) { \ + .type = IIO_VOLTAGE, \ + .indexed = 1, \ + .channel = (_chan), \ + .address = (_addr), \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE), \ + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .event_spec = (_alarm) ? xadc_voltage_events : NULL, \ + .num_event_specs = (_alarm) ? ARRAY_SIZE(xadc_voltage_events) : 0, \ + .scan_index = (_scan_index), \ + .scan_type = { \ + .sign = 'u', \ + .realbits = 12, \ + .storagebits = 16, \ + .shift = 4, \ + .endianness = IIO_CPU, \ + }, \ + .extend_name = _ext, \ +} + +static const struct iio_chan_spec xadc_channels[] = { + XADC_CHAN_TEMP(0, 8, XADC_REG_TEMP), + XADC_CHAN_VOLTAGE(0, 9, XADC_REG_VCCINT, "vccint", true), + XADC_CHAN_VOLTAGE(1, 10, XADC_REG_VCCINT, "vccaux", true), + XADC_CHAN_VOLTAGE(2, 14, XADC_REG_VCCBRAM, "vccbram", true), + XADC_CHAN_VOLTAGE(3, 5, XADC_REG_VCCPINT, "vccpint", true), + XADC_CHAN_VOLTAGE(4, 6, XADC_REG_VCCPAUX, "vccpaux", true), + XADC_CHAN_VOLTAGE(5, 7, XADC_REG_VCCO_DDR, "vccoddr", true), + XADC_CHAN_VOLTAGE(6, 12, XADC_REG_VREFP, "vrefp", false), + XADC_CHAN_VOLTAGE(7, 13, XADC_REG_VREFN, "vrefn", false), + XADC_CHAN_VOLTAGE(8, 11, XADC_REG_VPVN, NULL, false), + XADC_CHAN_VOLTAGE(9, 16, XADC_REG_VAUX(0), NULL, false), + XADC_CHAN_VOLTAGE(10, 17, XADC_REG_VAUX(1), NULL, false), + XADC_CHAN_VOLTAGE(11, 18, XADC_REG_VAUX(2), NULL, false), + XADC_CHAN_VOLTAGE(12, 19, XADC_REG_VAUX(3), NULL, false), + XADC_CHAN_VOLTAGE(13, 20, XADC_REG_VAUX(4), NULL, false), + XADC_CHAN_VOLTAGE(14, 21, XADC_REG_VAUX(5), NULL, false), + XADC_CHAN_VOLTAGE(15, 22, XADC_REG_VAUX(6), NULL, false), + XADC_CHAN_VOLTAGE(16, 23, XADC_REG_VAUX(7), NULL, false), + XADC_CHAN_VOLTAGE(17, 24, XADC_REG_VAUX(8), NULL, false), + XADC_CHAN_VOLTAGE(18, 25, XADC_REG_VAUX(9), NULL, false), + XADC_CHAN_VOLTAGE(19, 26, XADC_REG_VAUX(10), NULL, false), + XADC_CHAN_VOLTAGE(20, 27, XADC_REG_VAUX(11), NULL, false), + XADC_CHAN_VOLTAGE(21, 28, XADC_REG_VAUX(12), NULL, false), + XADC_CHAN_VOLTAGE(22, 29, XADC_REG_VAUX(13), NULL, false), + XADC_CHAN_VOLTAGE(23, 30, XADC_REG_VAUX(14), NULL, false), + XADC_CHAN_VOLTAGE(24, 31, XADC_REG_VAUX(15), NULL, false), +}; + +static const struct iio_info xadc_info = { + .read_raw = &xadc_read_raw, + .write_raw = &xadc_write_raw, + .read_event_config = &xadc_read_event_config, + .write_event_config = &xadc_write_event_config, + .read_event_value = &xadc_read_event_value, + .write_event_value = &xadc_write_event_value, + .update_scan_mode = &xadc_update_scan_mode, + .driver_module = THIS_MODULE, +}; + +static const struct of_device_id xadc_of_match_table[] = { + { .compatible = "xlnx,zynq-xadc-1.00.a", (void *)&xadc_zynq_ops }, + { .compatible = "xlnx,axi-xadc-1.00.a", (void *)&xadc_axi_ops }, + { }, +}; +MODULE_DEVICE_TABLE(of, xadc_of_match_table); + +static int xadc_parse_dt(struct iio_dev *indio_dev, struct device_node *np, + unsigned int *conf) +{ + struct xadc *xadc = iio_priv(indio_dev); + struct iio_chan_spec *channels, *chan; + struct device_node *chan_node, *child; + unsigned int num_channels; + const char *external_mux; + u32 ext_mux_chan; + int reg; + int ret; + + *conf = 0; + + ret = of_property_read_string(np, "xlnx,external-mux", &external_mux); + if (ret < 0 || strcasecmp(external_mux, "none") == 0) + xadc->external_mux_mode = XADC_EXTERNAL_MUX_NONE; + else if (strcasecmp(external_mux, "single") == 0) + xadc->external_mux_mode = XADC_EXTERNAL_MUX_SINGLE; + else if (strcasecmp(external_mux, "dual") == 0) + xadc->external_mux_mode = XADC_EXTERNAL_MUX_DUAL; + else + return -EINVAL; + + if (xadc->external_mux_mode != XADC_EXTERNAL_MUX_NONE) { + ret = of_property_read_u32(np, "xlnx,external-mux-channel", + &ext_mux_chan); + if (ret < 0) + return ret; + + if (xadc->external_mux_mode == XADC_EXTERNAL_MUX_SINGLE) { + if (ext_mux_chan == 0) + ext_mux_chan = XADC_REG_VPVN; + else if (ext_mux_chan <= 16) + ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1); + else + return -EINVAL; + } else { + if (ext_mux_chan > 0 && ext_mux_chan <= 8) + ext_mux_chan = XADC_REG_VAUX(ext_mux_chan - 1); + else + return -EINVAL; + } + + *conf |= XADC_CONF0_MUX | XADC_CONF0_CHAN(ext_mux_chan); + } + + channels = kmemdup(xadc_channels, sizeof(xadc_channels), GFP_KERNEL); + if (!channels) + return -ENOMEM; + + num_channels = 9; + chan = &channels[9]; + + chan_node = of_get_child_by_name(np, "xlnx,channels"); + if (chan_node) { + for_each_child_of_node(chan_node, child) { + if (num_channels >= ARRAY_SIZE(xadc_channels)) { + of_node_put(child); + break; + } + + ret = of_property_read_u32(child, "reg", ®); + if (ret || reg > 16) + continue; + + if (of_property_read_bool(child, "xlnx,bipolar")) + chan->scan_type.sign = 's'; + + if (reg == 0) { + chan->scan_index = 11; + chan->address = XADC_REG_VPVN; + } else { + chan->scan_index = 15 + reg; + chan->scan_index = XADC_REG_VAUX(reg - 1); + } + num_channels++; + chan++; + } + } + of_node_put(chan_node); + + indio_dev->num_channels = num_channels; + indio_dev->channels = krealloc(channels, sizeof(*channels) * + num_channels, GFP_KERNEL); + /* If we can't resize the channels array, just use the original */ + if (!indio_dev->channels) + indio_dev->channels = channels; + + return 0; +} + +static int xadc_probe(struct platform_device *pdev) +{ + const struct of_device_id *id; + struct iio_dev *indio_dev; + unsigned int bipolar_mask; + struct resource *mem; + unsigned int conf0; + struct xadc *xadc; + int ret; + int irq; + int i; + + if (!pdev->dev.of_node) + return -ENODEV; + + id = of_match_node(xadc_of_match_table, pdev->dev.of_node); + if (!id) + return -EINVAL; + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) + return -ENXIO; + + indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*xadc)); + if (!indio_dev) + return -ENOMEM; + + xadc = iio_priv(indio_dev); + xadc->ops = id->data; + init_completion(&xadc->completion); + mutex_init(&xadc->mutex); + spin_lock_init(&xadc->lock); + INIT_DELAYED_WORK(&xadc->zynq_unmask_work, xadc_zynq_unmask_worker); + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + xadc->base = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(xadc->base)) + return PTR_ERR(xadc->base); + + indio_dev->dev.parent = &pdev->dev; + indio_dev->dev.of_node = pdev->dev.of_node; + indio_dev->name = "xadc"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &xadc_info; + + ret = xadc_parse_dt(indio_dev, pdev->dev.of_node, &conf0); + if (ret) + goto err_device_free; + + if (xadc->ops->flags & XADC_FLAGS_BUFFERED) { + ret = iio_triggered_buffer_setup(indio_dev, + &iio_pollfunc_store_time, &xadc_trigger_handler, + &xadc_buffer_ops); + if (ret) + goto err_device_free; + + xadc->convst_trigger = xadc_alloc_trigger(indio_dev, "convst"); + if (IS_ERR(xadc->convst_trigger)) + goto err_triggered_buffer_cleanup; + xadc->samplerate_trigger = xadc_alloc_trigger(indio_dev, + "samplerate"); + if (IS_ERR(xadc->samplerate_trigger)) + goto err_free_convst_trigger; + } + + xadc->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(xadc->clk)) { + ret = PTR_ERR(xadc->clk); + goto err_free_samplerate_trigger; + } + clk_prepare_enable(xadc->clk); + + ret = xadc->ops->setup(pdev, indio_dev, irq); + if (ret) + goto err_free_samplerate_trigger; + + ret = request_threaded_irq(irq, xadc->ops->interrupt_handler, + xadc->ops->threaded_interrupt_handler, + 0, dev_name(&pdev->dev), indio_dev); + if (ret) + goto err_clk_disable_unprepare; + + for (i = 0; i < 16; i++) + xadc_read_adc_reg(xadc, XADC_REG_THRESHOLD(i), + &xadc->threshold[i]); + + ret = xadc_write_adc_reg(xadc, XADC_REG_CONF0, conf0); + if (ret) + goto err_free_irq; + + bipolar_mask = 0; + for (i = 0; i < indio_dev->num_channels; i++) { + if (indio_dev->channels[i].scan_type.sign == 's') + bipolar_mask |= BIT(indio_dev->channels[i].scan_index); + } + + ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(0), bipolar_mask); + if (ret) + goto err_free_irq; + ret = xadc_write_adc_reg(xadc, XADC_REG_INPUT_MODE(1), + bipolar_mask >> 16); + if (ret) + goto err_free_irq; + + /* Disable all alarms */ + xadc_update_adc_reg(xadc, XADC_REG_CONF1, XADC_CONF1_ALARM_MASK, + XADC_CONF1_ALARM_MASK); + + /* Set thresholds to min/max */ + for (i = 0; i < 16; i++) { + /* + * Set max voltage threshold and both temperature thresholds to + * 0xffff, min voltage threshold to 0. + */ + if (i % 8 < 4 || i == 7) + xadc->threshold[i] = 0xffff; + else + xadc->threshold[i] = 0; + xadc_write_adc_reg(xadc, XADC_REG_THRESHOLD(i), + xadc->threshold[i]); + } + + /* Go to non-buffered mode */ + xadc_postdisable(indio_dev); + + ret = iio_device_register(indio_dev); + if (ret) + goto err_free_irq; + + platform_set_drvdata(pdev, indio_dev); + + return 0; + +err_free_irq: + free_irq(irq, indio_dev); +err_free_samplerate_trigger: + if (xadc->ops->flags & XADC_FLAGS_BUFFERED) + iio_trigger_free(xadc->samplerate_trigger); +err_free_convst_trigger: + if (xadc->ops->flags & XADC_FLAGS_BUFFERED) + iio_trigger_free(xadc->convst_trigger); +err_triggered_buffer_cleanup: + if (xadc->ops->flags & XADC_FLAGS_BUFFERED) + iio_triggered_buffer_cleanup(indio_dev); +err_clk_disable_unprepare: + clk_disable_unprepare(xadc->clk); +err_device_free: + kfree(indio_dev->channels); + + return ret; +} + +static int xadc_remove(struct platform_device *pdev) +{ + struct iio_dev *indio_dev = platform_get_drvdata(pdev); + struct xadc *xadc = iio_priv(indio_dev); + int irq = platform_get_irq(pdev, 0); + + iio_device_unregister(indio_dev); + if (xadc->ops->flags & XADC_FLAGS_BUFFERED) { + iio_trigger_free(xadc->samplerate_trigger); + iio_trigger_free(xadc->convst_trigger); + iio_triggered_buffer_cleanup(indio_dev); + } + free_irq(irq, indio_dev); + clk_disable_unprepare(xadc->clk); + cancel_delayed_work(&xadc->zynq_unmask_work); + kfree(xadc->data); + kfree(indio_dev->channels); + + return 0; +} + +static struct platform_driver xadc_driver = { + .probe = xadc_probe, + .remove = xadc_remove, + .driver = { + .name = "xadc", + .owner = THIS_MODULE, + .of_match_table = xadc_of_match_table, + }, +}; +module_platform_driver(xadc_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); +MODULE_DESCRIPTION("Xilinx XADC IIO driver"); diff --git a/drivers/iio/adc/xilinx-xadc-events.c b/drivers/iio/adc/xilinx-xadc-events.c new file mode 100644 index 0000000..3e7f0d7 --- /dev/null +++ b/drivers/iio/adc/xilinx-xadc-events.c @@ -0,0 +1,254 @@ +/* + * Xilinx XADC driver + * + * Copyright 2013 Analog Devices Inc. + * Author: Lars-Peter Clauen <lars@metafoo.de> + * + * Licensed under the GPL-2. + */ + +#include <linux/iio/events.h> +#include <linux/iio/iio.h> +#include <linux/kernel.h> + +#include "xilinx-xadc.h" + +static const struct iio_chan_spec *xadc_event_to_channel( + struct iio_dev *indio_dev, unsigned int event) +{ + switch (event) { + case XADC_THRESHOLD_OT_MAX: + case XADC_THRESHOLD_TEMP_MAX: + return &indio_dev->channels[0]; + case XADC_THRESHOLD_VCCINT_MAX: + case XADC_THRESHOLD_VCCAUX_MAX: + return &indio_dev->channels[event]; + default: + return &indio_dev->channels[event-1]; + } +} + +static void xadc_handle_event(struct iio_dev *indio_dev, unsigned int event) +{ + const struct iio_chan_spec *chan; + unsigned int offset; + + /* Temperature threshold error, we don't handle this yet */ + if (event == 0) + return; + + if (event < 4) + offset = event; + else + offset = event + 4; + + chan = xadc_event_to_channel(indio_dev, event); + + if (chan->type == IIO_TEMP) { + /* + * The temperature channel only supports over-temperature + * events. + */ + iio_push_event(indio_dev, + IIO_UNMOD_EVENT_CODE(chan->type, chan->channel, + IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING), + iio_get_time_ns()); + } else { + /* + * For other channels we don't know whether it is a upper or + * lower threshold event. Userspace will have to check the + * channel value if it wants to know. + */ + iio_push_event(indio_dev, + IIO_UNMOD_EVENT_CODE(chan->type, chan->channel, + IIO_EV_TYPE_THRESH, IIO_EV_DIR_EITHER), + iio_get_time_ns()); + } +} + +void xadc_handle_events(struct iio_dev *indio_dev, unsigned long events) +{ + unsigned int i; + + for_each_set_bit(i, &events, 8) + xadc_handle_event(indio_dev, i); +} + +static unsigned xadc_get_threshold_offset(const struct iio_chan_spec *chan, + enum iio_event_direction dir) +{ + unsigned int offset; + + if (chan->type == IIO_TEMP) { + offset = XADC_THRESHOLD_OT_MAX; + } else { + if (chan->channel < 2) + offset = chan->channel + 1; + else + offset = chan->channel + 6; + } + + if (dir == IIO_EV_DIR_FALLING) + offset += 4; + + return offset; +} + +static unsigned int xadc_get_alarm_mask(const struct iio_chan_spec *chan) +{ + if (chan->type == IIO_TEMP) { + return XADC_ALARM_OT_MASK; + } else { + switch (chan->channel) { + case 0: + return XADC_ALARM_VCCINT_MASK; + case 1: + return XADC_ALARM_VCCAUX_MASK; + case 2: + return XADC_ALARM_VCCBRAM_MASK; + case 3: + return XADC_ALARM_VCCPINT_MASK; + case 4: + return XADC_ALARM_VCCPAUX_MASK; + case 5: + return XADC_ALARM_VCCODDR_MASK; + default: + /* We will never get here */ + return 0; + } + } +} + +int xadc_read_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir) +{ + struct xadc *xadc = iio_priv(indio_dev); + + return (bool)(xadc->alarm_mask & xadc_get_alarm_mask(chan)); +} + +int xadc_write_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, int state) +{ + unsigned int alarm = xadc_get_alarm_mask(chan); + struct xadc *xadc = iio_priv(indio_dev); + uint16_t cfg, old_cfg; + int ret; + + mutex_lock(&xadc->mutex); + + if (state) + xadc->alarm_mask |= alarm; + else + xadc->alarm_mask &= ~alarm; + + xadc->ops->update_alarm(xadc, xadc->alarm_mask); + + ret = _xadc_read_adc_reg(xadc, XADC_REG_CONF1, &cfg); + if (ret) + goto err_out; + + old_cfg = cfg; + cfg |= XADC_CONF1_ALARM_MASK; + cfg &= ~((xadc->alarm_mask & 0xf0) << 4); /* bram, pint, paux, ddr */ + cfg &= ~((xadc->alarm_mask & 0x08) >> 3); /* ot */ + cfg &= ~((xadc->alarm_mask & 0x07) << 1); /* temp, vccint, vccaux */ + if (old_cfg != cfg) + ret = _xadc_write_adc_reg(xadc, XADC_REG_CONF1, cfg); + +err_out: + mutex_unlock(&xadc->mutex); + + return ret; +} + +/* Register value is msb aligned, the lower 4 bits are ignored */ +#define XADC_THRESHOLD_VALUE_SHIFT 4 + +int xadc_read_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int *val, int *val2) +{ + unsigned int offset = xadc_get_threshold_offset(chan, dir); + struct xadc *xadc = iio_priv(indio_dev); + + switch (info) { + case IIO_EV_INFO_VALUE: + *val = xadc->threshold[offset]; + break; + case IIO_EV_INFO_HYSTERESIS: + *val = xadc->temp_hysteresis; + break; + default: + return -EINVAL; + } + + *val >>= XADC_THRESHOLD_VALUE_SHIFT; + + return IIO_VAL_INT; +} + +int xadc_write_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int val, int val2) +{ + unsigned int offset = xadc_get_threshold_offset(chan, dir); + struct xadc *xadc = iio_priv(indio_dev); + int ret = 0; + + val <<= XADC_THRESHOLD_VALUE_SHIFT; + + if (val < 0 || val > 0xffff) + return -EINVAL; + + mutex_lock(&xadc->mutex); + + switch (info) { + case IIO_EV_INFO_VALUE: + xadc->threshold[offset] = val; + break; + case IIO_EV_INFO_HYSTERESIS: + xadc->temp_hysteresis = val; + break; + default: + mutex_unlock(&xadc->mutex); + return -EINVAL; + } + + if (chan->type == IIO_TEMP) { + /* + * According to the datasheet we need to set the lower 4 bits to + * 0x3, otherwise 125 degree celsius will be used as the + * threshold. + */ + val |= 0x3; + + /* + * Since we store the hysteresis as relative (to the threshold) + * value, but the hardware expects an absolute value we need to + * recalcualte this value whenever the hysteresis or the + * threshold changes. + */ + if (xadc->threshold[offset] < xadc->temp_hysteresis) + xadc->threshold[offset + 4] = 0; + else + xadc->threshold[offset + 4] = xadc->threshold[offset] - + xadc->temp_hysteresis; + ret = _xadc_write_adc_reg(xadc, XADC_REG_THRESHOLD(offset + 4), + xadc->threshold[offset + 4]); + if (ret) + goto out_unlock; + } + + if (info == IIO_EV_INFO_VALUE) + ret = _xadc_write_adc_reg(xadc, XADC_REG_THRESHOLD(offset), val); + +out_unlock: + mutex_unlock(&xadc->mutex); + + return ret; +} diff --git a/drivers/iio/adc/xilinx-xadc.h b/drivers/iio/adc/xilinx-xadc.h new file mode 100644 index 0000000..c7487e8 --- /dev/null +++ b/drivers/iio/adc/xilinx-xadc.h @@ -0,0 +1,209 @@ +/* + * Xilinx XADC driver + * + * Copyright 2013 Analog Devices Inc. + * Author: Lars-Peter Clauen <lars@metafoo.de> + * + * Licensed under the GPL-2. + */ + +#ifndef __IIO_XILINX_XADC__ +#define __IIO_XILINX_XADC__ + +#include <linux/interrupt.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> + +struct iio_dev; +struct clk; +struct xadc_ops; +struct platform_device; + +void xadc_handle_events(struct iio_dev *indio_dev, unsigned long events); + +int xadc_read_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir); +int xadc_write_event_config(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, int state); +int xadc_read_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int *val, int *val2); +int xadc_write_event_value(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, enum iio_event_type type, + enum iio_event_direction dir, enum iio_event_info info, + int val, int val2); + +enum xadc_external_mux_mode { + XADC_EXTERNAL_MUX_NONE, + XADC_EXTERNAL_MUX_SINGLE, + XADC_EXTERNAL_MUX_DUAL, +}; + +struct xadc { + void __iomem *base; + struct clk *clk; + + const struct xadc_ops *ops; + + uint16_t threshold[16]; + uint16_t temp_hysteresis; + unsigned int alarm_mask; + + uint16_t *data; + + struct iio_trigger *trigger; + struct iio_trigger *convst_trigger; + struct iio_trigger *samplerate_trigger; + + enum xadc_external_mux_mode external_mux_mode; + + unsigned int zynq_alarm; + unsigned int zynq_masked_alarm; + unsigned int zynq_intmask; + struct delayed_work zynq_unmask_work; + + struct mutex mutex; + spinlock_t lock; + + struct completion completion; +}; + +struct xadc_ops { + int (*read)(struct xadc *, unsigned int, uint16_t *); + int (*write)(struct xadc *, unsigned int, uint16_t); + int (*setup)(struct platform_device *pdev, struct iio_dev *indio_dev, + int irq); + void (*update_alarm)(struct xadc *, unsigned int); + unsigned long (*get_dclk_rate)(struct xadc *); + irqreturn_t (*interrupt_handler)(int, void *); + irqreturn_t (*threaded_interrupt_handler)(int, void *); + + unsigned int flags; +}; + +static inline int _xadc_read_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t *val) +{ + lockdep_assert_held(&xadc->mutex); + return xadc->ops->read(xadc, reg, val); +} + +static inline int _xadc_write_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t val) +{ + lockdep_assert_held(&xadc->mutex); + return xadc->ops->write(xadc, reg, val); +} + +static inline int xadc_read_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t *val) +{ + int ret; + + mutex_lock(&xadc->mutex); + ret = _xadc_read_adc_reg(xadc, reg, val); + mutex_unlock(&xadc->mutex); + return ret; +} + +static inline int xadc_write_adc_reg(struct xadc *xadc, unsigned int reg, + uint16_t val) +{ + int ret; + + mutex_lock(&xadc->mutex); + ret = _xadc_write_adc_reg(xadc, reg, val); + mutex_unlock(&xadc->mutex); + return ret; +} + +/* XADC hardmacro register definitions */ +#define XADC_REG_TEMP 0x00 +#define XADC_REG_VCCINT 0x01 +#define XADC_REG_VCCAUX 0x02 +#define XADC_REG_VPVN 0x03 +#define XADC_REG_VREFP 0x04 +#define XADC_REG_VREFN 0x05 +#define XADC_REG_VCCBRAM 0x06 + +#define XADC_REG_VCCPINT 0x0d +#define XADC_REG_VCCPAUX 0x0e +#define XADC_REG_VCCO_DDR 0x0f +#define XADC_REG_VAUX(x) (0x10 + (x)) + +#define XADC_REG_MAX_TEMP 0x20 +#define XADC_REG_MAX_VCCINT 0x21 +#define XADC_REG_MAX_VCCAUX 0x22 +#define XADC_REG_MAX_VCCBRAM 0x23 +#define XADC_REG_MIN_TEMP 0x24 +#define XADC_REG_MIN_VCCINT 0x25 +#define XADC_REG_MIN_VCCAUX 0x26 +#define XADC_REG_MIN_VCCBRAM 0x27 +#define XADC_REG_MAX_VCCPINT 0x28 +#define XADC_REG_MAX_VCCPAUX 0x29 +#define XADC_REG_MAX_VCCO_DDR 0x2a +#define XADC_REG_MIN_VCCPINT 0x2b +#define XADC_REG_MIN_VCCPAUX 0x2c +#define XADC_REG_MIN_VCCO_DDR 0x2d + +#define XADC_REG_CONF0 0x40 +#define XADC_REG_CONF1 0x41 +#define XADC_REG_CONF2 0x42 +#define XADC_REG_SEQ(x) (0x48 + (x)) +#define XADC_REG_INPUT_MODE(x) (0x4c + (x)) +#define XADC_REG_THRESHOLD(x) (0x50 + (x)) + +#define XADC_REG_FLAG 0x3f + +#define XADC_CONF0_EC BIT(9) +#define XADC_CONF0_ACQ BIT(8) +#define XADC_CONF0_MUX BIT(11) +#define XADC_CONF0_CHAN(x) (x) + +#define XADC_CONF1_SEQ_MASK (0xf << 12) +#define XADC_CONF1_SEQ_DEFAULT (0 << 12) +#define XADC_CONF1_SEQ_SINGLE_PASS (1 << 12) +#define XADC_CONF1_SEQ_CONTINUOUS (2 << 12) +#define XADC_CONF1_SEQ_SINGLE_CHANNEL (3 << 12) +#define XADC_CONF1_SEQ_SIMULTANEOUS (4 << 12) +#define XADC_CONF1_SEQ_INDEPENDENT (8 << 12) +#define XADC_CONF1_ALARM_MASK 0x0f0f + +#define XADC_CONF2_DIV_MASK 0xff00 +#define XADC_CONF2_DIV_OFFSET 8 + +#define XADC_CONF2_PD_MASK (0x3 << 4) +#define XADC_CONF2_PD_NONE (0x0 << 4) +#define XADC_CONF2_PD_ADC_B (0x2 << 4) +#define XADC_CONF2_PD_BOTH (0x3 << 4) + +#define XADC_ALARM_TEMP_MASK BIT(0) +#define XADC_ALARM_VCCINT_MASK BIT(1) +#define XADC_ALARM_VCCAUX_MASK BIT(2) +#define XADC_ALARM_OT_MASK BIT(3) +#define XADC_ALARM_VCCBRAM_MASK BIT(4) +#define XADC_ALARM_VCCPINT_MASK BIT(5) +#define XADC_ALARM_VCCPAUX_MASK BIT(6) +#define XADC_ALARM_VCCODDR_MASK BIT(7) + +#define XADC_THRESHOLD_TEMP_MAX 0x0 +#define XADC_THRESHOLD_VCCINT_MAX 0x1 +#define XADC_THRESHOLD_VCCAUX_MAX 0x2 +#define XADC_THRESHOLD_OT_MAX 0x3 +#define XADC_THRESHOLD_TEMP_MIN 0x4 +#define XADC_THRESHOLD_VCCINT_MIN 0x5 +#define XADC_THRESHOLD_VCCAUX_MIN 0x6 +#define XADC_THRESHOLD_OT_MIN 0x7 +#define XADC_THRESHOLD_VCCBRAM_MAX 0x8 +#define XADC_THRESHOLD_VCCPINT_MAX 0x9 +#define XADC_THRESHOLD_VCCPAUX_MAX 0xa +#define XADC_THRESHOLD_VCCODDR_MAX 0xb +#define XADC_THRESHOLD_VCCBRAM_MIN 0xc +#define XADC_THRESHOLD_VCCPINT_MIN 0xd +#define XADC_THRESHOLD_VCCPAUX_MIN 0xe +#define XADC_THRESHOLD_VCCODDR_MIN 0xf + +#endif |