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path: root/drivers/spi/soft_spi.c
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Diffstat (limited to 'drivers/spi/soft_spi.c')
-rw-r--r--drivers/spi/soft_spi.c227
1 files changed, 149 insertions, 78 deletions
diff --git a/drivers/spi/soft_spi.c b/drivers/spi/soft_spi.c
index c969be3..5588036 100644
--- a/drivers/spi/soft_spi.c
+++ b/drivers/spi/soft_spi.c
@@ -1,4 +1,6 @@
/*
+ * Copyright (c) 2014 Google, Inc
+ *
* (C) Copyright 2002
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
*
@@ -9,94 +11,81 @@
*/
#include <common.h>
-#include <spi.h>
-
+#include <dm.h>
+#include <errno.h>
+#include <fdtdec.h>
#include <malloc.h>
+#include <spi.h>
+#include <asm/gpio.h>
-/*-----------------------------------------------------------------------
- * Definitions
- */
+DECLARE_GLOBAL_DATA_PTR;
-#ifdef DEBUG_SPI
-#define PRINTD(fmt,args...) printf (fmt ,##args)
-#else
-#define PRINTD(fmt,args...)
-#endif
+struct soft_spi_platdata {
+ struct fdt_gpio_state cs;
+ struct fdt_gpio_state sclk;
+ struct fdt_gpio_state mosi;
+ struct fdt_gpio_state miso;
+ int spi_delay_us;
+};
-struct soft_spi_slave {
- struct spi_slave slave;
+struct soft_spi_priv {
unsigned int mode;
};
-static inline struct soft_spi_slave *to_soft_spi(struct spi_slave *slave)
+static int soft_spi_scl(struct udevice *dev, int bit)
{
- return container_of(slave, struct soft_spi_slave, slave);
-}
+ struct soft_spi_platdata *plat = dev->platdata;
+ struct soft_spi_priv *priv = dev_get_priv(dev);
-/*=====================================================================*/
-/* Public Functions */
-/*=====================================================================*/
+ gpio_set_value(plat->sclk.gpio, priv->mode & SPI_CPOL ? bit : !bit);
-/*-----------------------------------------------------------------------
- * Initialization
- */
-void spi_init (void)
-{
-#ifdef SPI_INIT
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-
- SPI_INIT;
-#endif
+ return 0;
}
-struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
- unsigned int max_hz, unsigned int mode)
+static int soft_spi_sda(struct udevice *dev, int bit)
{
- struct soft_spi_slave *ss;
+ struct soft_spi_platdata *plat = dev->platdata;
- if (!spi_cs_is_valid(bus, cs))
- return NULL;
+ gpio_set_value(plat->mosi.gpio, bit);
- ss = spi_alloc_slave(struct soft_spi_slave, bus, cs);
- if (!ss)
- return NULL;
+ return 0;
+}
- ss->mode = mode;
+static int soft_spi_cs_activate(struct udevice *dev)
+{
+ struct soft_spi_platdata *plat = dev->platdata;
+ struct soft_spi_priv *priv = dev_get_priv(dev);
- /* TODO: Use max_hz to limit the SCK rate */
+ gpio_set_value(plat->cs.gpio, !(priv->mode & SPI_CS_HIGH));
+ gpio_set_value(plat->sclk.gpio, priv->mode & SPI_CPOL);
+ gpio_set_value(plat->cs.gpio, priv->mode & SPI_CS_HIGH);
- return &ss->slave;
+ return 0;
}
-void spi_free_slave(struct spi_slave *slave)
+static int soft_spi_cs_deactivate(struct udevice *dev)
{
- struct soft_spi_slave *ss = to_soft_spi(slave);
+ struct soft_spi_platdata *plat = dev->platdata;
+ struct soft_spi_priv *priv = dev_get_priv(dev);
- free(ss);
+ gpio_set_value(plat->cs.gpio, !(priv->mode & SPI_CS_HIGH));
+
+ return 0;
}
-int spi_claim_bus(struct spi_slave *slave)
+static int soft_spi_claim_bus(struct udevice *dev)
{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
-
/*
* Make sure the SPI clock is in idle state as defined for
* this slave.
*/
- if (ss->mode & SPI_CPOL)
- SPI_SCL(1);
- else
- SPI_SCL(0);
-
- return 0;
+ return soft_spi_scl(dev, 0);
}
-void spi_release_bus(struct spi_slave *slave)
+static int soft_spi_release_bus(struct udevice *dev)
{
/* Nothing to do */
+ return 0;
}
/*-----------------------------------------------------------------------
@@ -111,28 +100,27 @@ void spi_release_bus(struct spi_slave *slave)
* input data overwrites the output data (since both are buffered by
* temporary variables, this is OK).
*/
-int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
- const void *dout, void *din, unsigned long flags)
+static int soft_spi_xfer(struct udevice *dev, unsigned int bitlen,
+ const void *dout, void *din, unsigned long flags)
{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
+ struct soft_spi_priv *priv = dev_get_priv(dev);
+ struct soft_spi_platdata *plat = dev->platdata;
uchar tmpdin = 0;
uchar tmpdout = 0;
const u8 *txd = dout;
u8 *rxd = din;
- int cpol = ss->mode & SPI_CPOL;
- int cpha = ss->mode & SPI_CPHA;
+ int cpol = priv->mode & SPI_CPOL;
+ int cpha = priv->mode & SPI_CPHA;
unsigned int j;
- PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
- slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);
+ debug("spi_xfer: slave %s:%s dout %08X din %08X bitlen %u\n",
+ dev->parent->name, dev->name, *(uint *)txd, *(uint *)rxd,
+ bitlen);
if (flags & SPI_XFER_BEGIN)
- spi_cs_activate(slave);
+ soft_spi_cs_activate(dev);
- for(j = 0; j < bitlen; j++) {
+ for (j = 0; j < bitlen; j++) {
/*
* Check if it is time to work on a new byte.
*/
@@ -141,7 +129,7 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
tmpdout = *txd++;
else
tmpdout = 0;
- if(j != 0) {
+ if (j != 0) {
if (rxd)
*rxd++ = tmpdin;
}
@@ -149,19 +137,19 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
}
if (!cpha)
- SPI_SCL(!cpol);
- SPI_SDA(tmpdout & 0x80);
- SPI_DELAY;
+ soft_spi_scl(dev, !cpol);
+ soft_spi_sda(dev, tmpdout & 0x80);
+ udelay(plat->spi_delay_us);
if (cpha)
- SPI_SCL(!cpol);
+ soft_spi_scl(dev, !cpol);
else
- SPI_SCL(cpol);
+ soft_spi_scl(dev, cpol);
tmpdin <<= 1;
- tmpdin |= SPI_READ;
+ tmpdin |= gpio_get_value(plat->miso.gpio);
tmpdout <<= 1;
- SPI_DELAY;
+ udelay(plat->spi_delay_us);
if (cpha)
- SPI_SCL(cpol);
+ soft_spi_scl(dev, cpol);
}
/*
* If the number of bits isn't a multiple of 8, shift the last
@@ -175,7 +163,90 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
}
if (flags & SPI_XFER_END)
- spi_cs_deactivate(slave);
+ soft_spi_cs_deactivate(dev);
- return(0);
+ return 0;
}
+
+static int soft_spi_set_speed(struct udevice *dev, unsigned int speed)
+{
+ /* Accept any speed */
+ return 0;
+}
+
+static int soft_spi_set_mode(struct udevice *dev, unsigned int mode)
+{
+ struct soft_spi_priv *priv = dev_get_priv(dev);
+
+ priv->mode = mode;
+
+ return 0;
+}
+
+static int soft_spi_child_pre_probe(struct udevice *dev)
+{
+ struct spi_slave *slave = dev_get_parentdata(dev);
+
+ slave->dev = dev;
+ return spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, slave);
+}
+
+static const struct dm_spi_ops soft_spi_ops = {
+ .claim_bus = soft_spi_claim_bus,
+ .release_bus = soft_spi_release_bus,
+ .xfer = soft_spi_xfer,
+ .set_speed = soft_spi_set_speed,
+ .set_mode = soft_spi_set_mode,
+};
+
+static int soft_spi_ofdata_to_platdata(struct udevice *dev)
+{
+ struct soft_spi_platdata *plat = dev->platdata;
+ const void *blob = gd->fdt_blob;
+ int node = dev->of_offset;
+
+ if (fdtdec_decode_gpio(blob, node, "cs-gpio", &plat->cs) ||
+ fdtdec_decode_gpio(blob, node, "sclk-gpio", &plat->sclk) ||
+ fdtdec_decode_gpio(blob, node, "mosi-gpio", &plat->mosi) ||
+ fdtdec_decode_gpio(blob, node, "miso-gpio", &plat->miso))
+ return -EINVAL;
+ plat->spi_delay_us = fdtdec_get_int(blob, node, "spi-delay-us", 0);
+
+ return 0;
+}
+
+static int soft_spi_probe(struct udevice *dev)
+{
+ struct spi_slave *slave = dev_get_parentdata(dev);
+ struct soft_spi_platdata *plat = dev->platdata;
+
+ gpio_request(plat->cs.gpio, "soft_spi_cs");
+ gpio_request(plat->sclk.gpio, "soft_spi_sclk");
+ gpio_request(plat->mosi.gpio, "soft_spi_mosi");
+ gpio_request(plat->miso.gpio, "soft_spi_miso");
+
+ gpio_direction_output(plat->sclk.gpio, slave->mode & SPI_CPOL);
+ gpio_direction_output(plat->mosi.gpio, 1);
+ gpio_direction_input(plat->miso.gpio);
+ gpio_direction_output(plat->cs.gpio, !(slave->mode & SPI_CS_HIGH));
+
+ return 0;
+}
+
+static const struct udevice_id soft_spi_ids[] = {
+ { .compatible = "u-boot,soft-spi" },
+ { }
+};
+
+U_BOOT_DRIVER(soft_spi) = {
+ .name = "soft_spi",
+ .id = UCLASS_SPI,
+ .of_match = soft_spi_ids,
+ .ops = &soft_spi_ops,
+ .ofdata_to_platdata = soft_spi_ofdata_to_platdata,
+ .platdata_auto_alloc_size = sizeof(struct soft_spi_platdata),
+ .priv_auto_alloc_size = sizeof(struct soft_spi_priv),
+ .per_child_auto_alloc_size = sizeof(struct spi_slave),
+ .probe = soft_spi_probe,
+ .child_pre_probe = soft_spi_child_pre_probe,
+};