diff options
author | Alexander Shiyan <shc_work@mail.ru> | 2012-08-06 15:42:32 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-08-16 19:12:25 (GMT) |
commit | f65444187a66bf54af32a10902877dd0326456d1 (patch) | |
tree | 9458139d0c7dd538d68cf6fa02e5ad4542162d83 /drivers/tty/serial/max3107.c | |
parent | 9574f36fb801035f6ab0fbb1b53ce2c12c17d100 (diff) | |
download | linux-fsl-qoriq-f65444187a66bf54af32a10902877dd0326456d1.tar.xz |
serial: New serial driver MAX310X
This driver is a replacement for a MAX3107 driver with a lot of
improvements and new features.
The main differences from the old version:
- Using the regmap.
- Using devm_XXX-related functions.
- The use of threaded IRQ with IRQF_ONESHOT flag allows the driver to
the hardware that supports only level IRQ.
- Improved error handling of serial port, improved FIFO handling,
improved hardware & software flow control.
- Advanced flags allows turn on RS-485 mode (Auto direction control).
- Ability to load multiple instances of drivers.
- Added support for MAX3108.
- GPIO support.
- Driver is quite ready for adding I2C support and support other ICs
with compatible registers set (MAX3109, MAX14830).
Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/max3107.c')
-rw-r--r-- | drivers/tty/serial/max3107.c | 1215 |
1 files changed, 0 insertions, 1215 deletions
diff --git a/drivers/tty/serial/max3107.c b/drivers/tty/serial/max3107.c deleted file mode 100644 index 17c7ba8..0000000 --- a/drivers/tty/serial/max3107.c +++ /dev/null @@ -1,1215 +0,0 @@ -/* - * max3107.c - spi uart protocol driver for Maxim 3107 - * Based on max3100.c - * by Christian Pellegrin <chripell@evolware.org> - * and max3110.c - * by Feng Tang <feng.tang@intel.com> - * - * Copyright (C) Aavamobile 2009 - * - * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - * - */ - -#include <linux/delay.h> -#include <linux/device.h> -#include <linux/serial_core.h> -#include <linux/serial.h> -#include <linux/tty.h> -#include <linux/tty_flip.h> -#include <linux/gpio.h> -#include <linux/spi/spi.h> -#include <linux/freezer.h> -#include <linux/module.h> -#include "max3107.h" - -static const struct baud_table brg26_ext[] = { - { 300, MAX3107_BRG26_B300 }, - { 600, MAX3107_BRG26_B600 }, - { 1200, MAX3107_BRG26_B1200 }, - { 2400, MAX3107_BRG26_B2400 }, - { 4800, MAX3107_BRG26_B4800 }, - { 9600, MAX3107_BRG26_B9600 }, - { 19200, MAX3107_BRG26_B19200 }, - { 57600, MAX3107_BRG26_B57600 }, - { 115200, MAX3107_BRG26_B115200 }, - { 230400, MAX3107_BRG26_B230400 }, - { 460800, MAX3107_BRG26_B460800 }, - { 921600, MAX3107_BRG26_B921600 }, - { 0, 0 } -}; - -static const struct baud_table brg13_int[] = { - { 300, MAX3107_BRG13_IB300 }, - { 600, MAX3107_BRG13_IB600 }, - { 1200, MAX3107_BRG13_IB1200 }, - { 2400, MAX3107_BRG13_IB2400 }, - { 4800, MAX3107_BRG13_IB4800 }, - { 9600, MAX3107_BRG13_IB9600 }, - { 19200, MAX3107_BRG13_IB19200 }, - { 57600, MAX3107_BRG13_IB57600 }, - { 115200, MAX3107_BRG13_IB115200 }, - { 230400, MAX3107_BRG13_IB230400 }, - { 460800, MAX3107_BRG13_IB460800 }, - { 921600, MAX3107_BRG13_IB921600 }, - { 0, 0 } -}; - -static u32 get_new_brg(int baud, struct max3107_port *s) -{ - int i; - const struct baud_table *baud_tbl = s->baud_tbl; - - for (i = 0; i < 13; i++) { - if (baud == baud_tbl[i].baud) - return baud_tbl[i].new_brg; - } - - return 0; -} - -/* Perform SPI transfer for write/read of device register(s) */ -int max3107_rw(struct max3107_port *s, u8 *tx, u8 *rx, int len) -{ - struct spi_message spi_msg; - struct spi_transfer spi_xfer; - - /* Initialize SPI ,message */ - spi_message_init(&spi_msg); - - /* Initialize SPI transfer */ - memset(&spi_xfer, 0, sizeof spi_xfer); - spi_xfer.len = len; - spi_xfer.tx_buf = tx; - spi_xfer.rx_buf = rx; - spi_xfer.speed_hz = MAX3107_SPI_SPEED; - - /* Add SPI transfer to SPI message */ - spi_message_add_tail(&spi_xfer, &spi_msg); - -#ifdef DBG_TRACE_SPI_DATA - { - int i; - pr_info("tx len %d:\n", spi_xfer.len); - for (i = 0 ; i < spi_xfer.len && i < 32 ; i++) - pr_info(" %x", ((u8 *)spi_xfer.tx_buf)[i]); - pr_info("\n"); - } -#endif - - /* Perform synchronous SPI transfer */ - if (spi_sync(s->spi, &spi_msg)) { - dev_err(&s->spi->dev, "spi_sync failure\n"); - return -EIO; - } - -#ifdef DBG_TRACE_SPI_DATA - if (spi_xfer.rx_buf) { - int i; - pr_info("rx len %d:\n", spi_xfer.len); - for (i = 0 ; i < spi_xfer.len && i < 32 ; i++) - pr_info(" %x", ((u8 *)spi_xfer.rx_buf)[i]); - pr_info("\n"); - } -#endif - return 0; -} -EXPORT_SYMBOL_GPL(max3107_rw); - -/* Puts received data to circular buffer */ -static void put_data_to_circ_buf(struct max3107_port *s, unsigned char *data, - int len) -{ - struct uart_port *port = &s->port; - struct tty_struct *tty; - - if (!port->state) - return; - - tty = port->state->port.tty; - if (!tty) - return; - - /* Insert received data */ - tty_insert_flip_string(tty, data, len); - /* Update RX counter */ - port->icount.rx += len; -} - -/* Handle data receiving */ -static void max3107_handlerx(struct max3107_port *s, u16 rxlvl) -{ - int i; - int j; - int len; /* SPI transfer buffer length */ - u16 *buf; - u8 *valid_str; - - if (!s->rx_enabled) - /* RX is disabled */ - return; - - if (rxlvl == 0) { - /* RX fifo is empty */ - return; - } else if (rxlvl >= MAX3107_RX_FIFO_SIZE) { - dev_warn(&s->spi->dev, "Possible RX FIFO overrun %d\n", rxlvl); - /* Ensure sanity of RX level */ - rxlvl = MAX3107_RX_FIFO_SIZE; - } - if ((s->rxbuf == 0) || (s->rxstr == 0)) { - dev_warn(&s->spi->dev, "Rx buffer/str isn't ready\n"); - return; - } - buf = s->rxbuf; - valid_str = s->rxstr; - while (rxlvl) { - pr_debug("rxlvl %d\n", rxlvl); - /* Clear buffer */ - memset(buf, 0, sizeof(u16) * (MAX3107_RX_FIFO_SIZE + 2)); - len = 0; - if (s->irqen_reg & MAX3107_IRQ_RXFIFO_BIT) { - /* First disable RX FIFO interrupt */ - pr_debug("Disabling RX INT\n"); - buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG); - s->irqen_reg &= ~MAX3107_IRQ_RXFIFO_BIT; - buf[0] |= s->irqen_reg; - len++; - } - /* Just increase the length by amount of words in FIFO since - * buffer was zeroed and SPI transfer of 0x0000 means reading - * from RX FIFO - */ - len += rxlvl; - /* Append RX level query */ - buf[len] = MAX3107_RXFIFOLVL_REG; - len++; - - /* Perform the SPI transfer */ - if (max3107_rw(s, (u8 *)buf, (u8 *)buf, len * 2)) { - dev_err(&s->spi->dev, "SPI transfer for RX h failed\n"); - return; - } - - /* Skip RX FIFO interrupt disabling word if it was added */ - j = ((len - 1) - rxlvl); - /* Read received words */ - for (i = 0; i < rxlvl; i++, j++) - valid_str[i] = (u8)buf[j]; - put_data_to_circ_buf(s, valid_str, rxlvl); - /* Get new RX level */ - rxlvl = (buf[len - 1] & MAX3107_SPI_RX_DATA_MASK); - } - - if (s->rx_enabled) { - /* RX still enabled, re-enable RX FIFO interrupt */ - pr_debug("Enabling RX INT\n"); - buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG); - s->irqen_reg |= MAX3107_IRQ_RXFIFO_BIT; - buf[0] |= s->irqen_reg; - if (max3107_rw(s, (u8 *)buf, NULL, 2)) - dev_err(&s->spi->dev, "RX FIFO INT enabling failed\n"); - } - - /* Push the received data to receivers */ - if (s->port.state->port.tty) - tty_flip_buffer_push(s->port.state->port.tty); -} - - -/* Handle data sending */ -static void max3107_handletx(struct max3107_port *s) -{ - struct circ_buf *xmit = &s->port.state->xmit; - int i; - unsigned long flags; - int len; /* SPI transfer buffer length */ - u16 *buf; - - if (!s->tx_fifo_empty) - /* Don't send more data before previous data is sent */ - return; - - if (uart_circ_empty(xmit) || uart_tx_stopped(&s->port)) - /* No data to send or TX is stopped */ - return; - - if (!s->txbuf) { - dev_warn(&s->spi->dev, "Txbuf isn't ready\n"); - return; - } - buf = s->txbuf; - /* Get length of data pending in circular buffer */ - len = uart_circ_chars_pending(xmit); - if (len) { - /* Limit to size of TX FIFO */ - if (len > MAX3107_TX_FIFO_SIZE) - len = MAX3107_TX_FIFO_SIZE; - - pr_debug("txlen %d\n", len); - - /* Update TX counter */ - s->port.icount.tx += len; - - /* TX FIFO will no longer be empty */ - s->tx_fifo_empty = 0; - - i = 0; - if (s->irqen_reg & MAX3107_IRQ_TXEMPTY_BIT) { - /* First disable TX empty interrupt */ - pr_debug("Disabling TE INT\n"); - buf[i] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG); - s->irqen_reg &= ~MAX3107_IRQ_TXEMPTY_BIT; - buf[i] |= s->irqen_reg; - i++; - len++; - } - /* Add data to send */ - spin_lock_irqsave(&s->port.lock, flags); - for ( ; i < len ; i++) { - buf[i] = (MAX3107_WRITE_BIT | MAX3107_THR_REG); - buf[i] |= ((u16)xmit->buf[xmit->tail] & - MAX3107_SPI_TX_DATA_MASK); - xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); - } - spin_unlock_irqrestore(&s->port.lock, flags); - if (!(s->irqen_reg & MAX3107_IRQ_TXEMPTY_BIT)) { - /* Enable TX empty interrupt */ - pr_debug("Enabling TE INT\n"); - buf[i] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG); - s->irqen_reg |= MAX3107_IRQ_TXEMPTY_BIT; - buf[i] |= s->irqen_reg; - i++; - len++; - } - if (!s->tx_enabled) { - /* Enable TX */ - pr_debug("Enable TX\n"); - buf[i] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG); - spin_lock_irqsave(&s->data_lock, flags); - s->mode1_reg &= ~MAX3107_MODE1_TXDIS_BIT; - buf[i] |= s->mode1_reg; - spin_unlock_irqrestore(&s->data_lock, flags); - s->tx_enabled = 1; - i++; - len++; - } - - /* Perform the SPI transfer */ - if (max3107_rw(s, (u8 *)buf, NULL, len*2)) { - dev_err(&s->spi->dev, - "SPI transfer TX handling failed\n"); - return; - } - } - - /* Indicate wake up if circular buffer is getting low on data */ - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&s->port); - -} - -/* Handle interrupts - * Also reads and returns current RX FIFO level - */ -static u16 handle_interrupt(struct max3107_port *s) -{ - u16 buf[4]; /* Buffer for SPI transfers */ - u8 irq_status; - u16 rx_level; - unsigned long flags; - - /* Read IRQ status register */ - buf[0] = MAX3107_IRQSTS_REG; - /* Read status IRQ status register */ - buf[1] = MAX3107_STS_IRQSTS_REG; - /* Read LSR IRQ status register */ - buf[2] = MAX3107_LSR_IRQSTS_REG; - /* Query RX level */ - buf[3] = MAX3107_RXFIFOLVL_REG; - - if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 8)) { - dev_err(&s->spi->dev, - "SPI transfer for INTR handling failed\n"); - return 0; - } - - irq_status = (u8)buf[0]; - pr_debug("IRQSTS %x\n", irq_status); - rx_level = (buf[3] & MAX3107_SPI_RX_DATA_MASK); - - if (irq_status & MAX3107_IRQ_LSR_BIT) { - /* LSR interrupt */ - if (buf[2] & MAX3107_LSR_RXTO_BIT) - /* RX timeout interrupt, - * handled by normal RX handling - */ - pr_debug("RX TO INT\n"); - } - - if (irq_status & MAX3107_IRQ_TXEMPTY_BIT) { - /* Tx empty interrupt, - * disable TX and set tx_fifo_empty flag - */ - pr_debug("TE INT, disabling TX\n"); - buf[0] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG); - spin_lock_irqsave(&s->data_lock, flags); - s->mode1_reg |= MAX3107_MODE1_TXDIS_BIT; - buf[0] |= s->mode1_reg; - spin_unlock_irqrestore(&s->data_lock, flags); - if (max3107_rw(s, (u8 *)buf, NULL, 2)) - dev_err(&s->spi->dev, "SPI transfer TX dis failed\n"); - s->tx_enabled = 0; - s->tx_fifo_empty = 1; - } - - if (irq_status & MAX3107_IRQ_RXFIFO_BIT) - /* RX FIFO interrupt, - * handled by normal RX handling - */ - pr_debug("RFIFO INT\n"); - - /* Return RX level */ - return rx_level; -} - -/* Trigger work thread*/ -static void max3107_dowork(struct max3107_port *s) -{ - if (!work_pending(&s->work) && !freezing(current) && !s->suspended) - queue_work(s->workqueue, &s->work); - else - dev_warn(&s->spi->dev, "interrup isn't serviced normally!\n"); -} - -/* Work thread */ -static void max3107_work(struct work_struct *w) -{ - struct max3107_port *s = container_of(w, struct max3107_port, work); - u16 rxlvl = 0; - int len; /* SPI transfer buffer length */ - u16 buf[5]; /* Buffer for SPI transfers */ - unsigned long flags; - - /* Start by reading current RX FIFO level */ - buf[0] = MAX3107_RXFIFOLVL_REG; - if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) { - dev_err(&s->spi->dev, "SPI transfer RX lev failed\n"); - rxlvl = 0; - } else { - rxlvl = (buf[0] & MAX3107_SPI_RX_DATA_MASK); - } - - do { - pr_debug("rxlvl %d\n", rxlvl); - - /* Handle RX */ - max3107_handlerx(s, rxlvl); - rxlvl = 0; - - if (s->handle_irq) { - /* Handle pending interrupts - * We also get new RX FIFO level since new data may - * have been received while pushing received data to - * receivers - */ - s->handle_irq = 0; - rxlvl = handle_interrupt(s); - } - - /* Handle TX */ - max3107_handletx(s); - - /* Handle configuration changes */ - len = 0; - spin_lock_irqsave(&s->data_lock, flags); - if (s->mode1_commit) { - pr_debug("mode1_commit\n"); - buf[len] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG); - buf[len++] |= s->mode1_reg; - s->mode1_commit = 0; - } - if (s->lcr_commit) { - pr_debug("lcr_commit\n"); - buf[len] = (MAX3107_WRITE_BIT | MAX3107_LCR_REG); - buf[len++] |= s->lcr_reg; - s->lcr_commit = 0; - } - if (s->brg_commit) { - pr_debug("brg_commit\n"); - buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVMSB_REG); - buf[len++] |= ((s->brg_cfg >> 16) & - MAX3107_SPI_TX_DATA_MASK); - buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVLSB_REG); - buf[len++] |= ((s->brg_cfg >> 8) & - MAX3107_SPI_TX_DATA_MASK); - buf[len] = (MAX3107_WRITE_BIT | MAX3107_BRGCFG_REG); - buf[len++] |= ((s->brg_cfg) & 0xff); - s->brg_commit = 0; - } - spin_unlock_irqrestore(&s->data_lock, flags); - - if (len > 0) { - if (max3107_rw(s, (u8 *)buf, NULL, len * 2)) - dev_err(&s->spi->dev, - "SPI transfer config failed\n"); - } - - /* Reloop if interrupt handling indicated data in RX FIFO */ - } while (rxlvl); - -} - -/* Set sleep mode */ -static void max3107_set_sleep(struct max3107_port *s, int mode) -{ - u16 buf[1]; /* Buffer for SPI transfer */ - unsigned long flags; - pr_debug("enter, mode %d\n", mode); - - buf[0] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG); - spin_lock_irqsave(&s->data_lock, flags); - switch (mode) { - case MAX3107_DISABLE_FORCED_SLEEP: - s->mode1_reg &= ~MAX3107_MODE1_FORCESLEEP_BIT; - break; - case MAX3107_ENABLE_FORCED_SLEEP: - s->mode1_reg |= MAX3107_MODE1_FORCESLEEP_BIT; - break; - case MAX3107_DISABLE_AUTOSLEEP: - s->mode1_reg &= ~MAX3107_MODE1_AUTOSLEEP_BIT; - break; - case MAX3107_ENABLE_AUTOSLEEP: - s->mode1_reg |= MAX3107_MODE1_AUTOSLEEP_BIT; - break; - default: - spin_unlock_irqrestore(&s->data_lock, flags); - dev_warn(&s->spi->dev, "invalid sleep mode\n"); - return; - } - buf[0] |= s->mode1_reg; - spin_unlock_irqrestore(&s->data_lock, flags); - - if (max3107_rw(s, (u8 *)buf, NULL, 2)) - dev_err(&s->spi->dev, "SPI transfer sleep mode failed\n"); - - if (mode == MAX3107_DISABLE_AUTOSLEEP || - mode == MAX3107_DISABLE_FORCED_SLEEP) - msleep(MAX3107_WAKEUP_DELAY); -} - -/* Perform full register initialization */ -static void max3107_register_init(struct max3107_port *s) -{ - u16 buf[11]; /* Buffer for SPI transfers */ - - /* 1. Configure baud rate, 9600 as default */ - s->baud = 9600; - /* the below is default*/ - if (s->ext_clk) { - s->brg_cfg = MAX3107_BRG26_B9600; - s->baud_tbl = (struct baud_table *)brg26_ext; - } else { - s->brg_cfg = MAX3107_BRG13_IB9600; - s->baud_tbl = (struct baud_table *)brg13_int; - } - - if (s->pdata->init) - s->pdata->init(s); - - buf[0] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVMSB_REG) - | ((s->brg_cfg >> 16) & MAX3107_SPI_TX_DATA_MASK); - buf[1] = (MAX3107_WRITE_BIT | MAX3107_BRGDIVLSB_REG) - | ((s->brg_cfg >> 8) & MAX3107_SPI_TX_DATA_MASK); - buf[2] = (MAX3107_WRITE_BIT | MAX3107_BRGCFG_REG) - | ((s->brg_cfg) & 0xff); - - /* 2. Configure LCR register, 8N1 mode by default */ - s->lcr_reg = MAX3107_LCR_WORD_LEN_8; - buf[3] = (MAX3107_WRITE_BIT | MAX3107_LCR_REG) - | s->lcr_reg; - - /* 3. Configure MODE 1 register */ - s->mode1_reg = 0; - /* Enable IRQ pin */ - s->mode1_reg |= MAX3107_MODE1_IRQSEL_BIT; - /* Disable TX */ - s->mode1_reg |= MAX3107_MODE1_TXDIS_BIT; - s->tx_enabled = 0; - /* RX is enabled */ - s->rx_enabled = 1; - buf[4] = (MAX3107_WRITE_BIT | MAX3107_MODE1_REG) - | s->mode1_reg; - - /* 4. Configure MODE 2 register */ - buf[5] = (MAX3107_WRITE_BIT | MAX3107_MODE2_REG); - if (s->loopback) { - /* Enable loopback */ - buf[5] |= MAX3107_MODE2_LOOPBACK_BIT; - } - /* Reset FIFOs */ - buf[5] |= MAX3107_MODE2_FIFORST_BIT; - s->tx_fifo_empty = 1; - - /* 5. Configure FIFO trigger level register */ - buf[6] = (MAX3107_WRITE_BIT | MAX3107_FIFOTRIGLVL_REG); - /* RX FIFO trigger for 16 words, TX FIFO trigger not used */ - buf[6] |= (MAX3107_FIFOTRIGLVL_RX(16) | MAX3107_FIFOTRIGLVL_TX(0)); - - /* 6. Configure flow control levels */ - buf[7] = (MAX3107_WRITE_BIT | MAX3107_FLOWLVL_REG); - /* Flow control halt level 96, resume level 48 */ - buf[7] |= (MAX3107_FLOWLVL_RES(48) | MAX3107_FLOWLVL_HALT(96)); - - /* 7. Configure flow control */ - buf[8] = (MAX3107_WRITE_BIT | MAX3107_FLOWCTRL_REG); - /* Enable auto CTS and auto RTS flow control */ - buf[8] |= (MAX3107_FLOWCTRL_AUTOCTS_BIT | MAX3107_FLOWCTRL_AUTORTS_BIT); - - /* 8. Configure RX timeout register */ - buf[9] = (MAX3107_WRITE_BIT | MAX3107_RXTO_REG); - /* Timeout after 48 character intervals */ - buf[9] |= 0x0030; - - /* 9. Configure LSR interrupt enable register */ - buf[10] = (MAX3107_WRITE_BIT | MAX3107_LSR_IRQEN_REG); - /* Enable RX timeout interrupt */ - buf[10] |= MAX3107_LSR_RXTO_BIT; - - /* Perform SPI transfer */ - if (max3107_rw(s, (u8 *)buf, NULL, 22)) - dev_err(&s->spi->dev, "SPI transfer for init failed\n"); - - /* 10. Clear IRQ status register by reading it */ - buf[0] = MAX3107_IRQSTS_REG; - - /* 11. Configure interrupt enable register */ - /* Enable LSR interrupt */ - s->irqen_reg = MAX3107_IRQ_LSR_BIT; - /* Enable RX FIFO interrupt */ - s->irqen_reg |= MAX3107_IRQ_RXFIFO_BIT; - buf[1] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG) - | s->irqen_reg; - - /* 12. Clear FIFO reset that was set in step 6 */ - buf[2] = (MAX3107_WRITE_BIT | MAX3107_MODE2_REG); - if (s->loopback) { - /* Keep loopback enabled */ - buf[2] |= MAX3107_MODE2_LOOPBACK_BIT; - } - - /* Perform SPI transfer */ - if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 6)) - dev_err(&s->spi->dev, "SPI transfer for init failed\n"); - -} - -/* IRQ handler */ -static irqreturn_t max3107_irq(int irqno, void *dev_id) -{ - struct max3107_port *s = dev_id; - - if (irqno != s->spi->irq) { - /* Unexpected IRQ */ - return IRQ_NONE; - } - - /* Indicate irq */ - s->handle_irq = 1; - - /* Trigger work thread */ - max3107_dowork(s); - - return IRQ_HANDLED; -} - -/* HW suspension function - * - * Currently autosleep is used to decrease current consumption, alternative - * approach would be to set the chip to reset mode if UART is not being - * used but that would mess the GPIOs - * - */ -void max3107_hw_susp(struct max3107_port *s, int suspend) -{ - pr_debug("enter, suspend %d\n", suspend); - - if (suspend) { - /* Suspend requested, - * enable autosleep to decrease current consumption - */ - s->suspended = 1; - max3107_set_sleep(s, MAX3107_ENABLE_AUTOSLEEP); - } else { - /* Resume requested, - * disable autosleep - */ - s->suspended = 0; - max3107_set_sleep(s, MAX3107_DISABLE_AUTOSLEEP); - } -} -EXPORT_SYMBOL_GPL(max3107_hw_susp); - -/* Modem status IRQ enabling */ -static void max3107_enable_ms(struct uart_port *port) -{ - /* Modem status not supported */ -} - -/* Data send function */ -static void max3107_start_tx(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - - /* Trigger work thread for sending data */ - max3107_dowork(s); -} - -/* Function for checking that there is no pending transfers */ -static unsigned int max3107_tx_empty(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - - pr_debug("returning %d\n", - (s->tx_fifo_empty && uart_circ_empty(&s->port.state->xmit))); - return s->tx_fifo_empty && uart_circ_empty(&s->port.state->xmit); -} - -/* Function for stopping RX */ -static void max3107_stop_rx(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - unsigned long flags; - - /* Set RX disabled in MODE 1 register */ - spin_lock_irqsave(&s->data_lock, flags); - s->mode1_reg |= MAX3107_MODE1_RXDIS_BIT; - s->mode1_commit = 1; - spin_unlock_irqrestore(&s->data_lock, flags); - /* Set RX disabled */ - s->rx_enabled = 0; - /* Trigger work thread for doing the actual configuration change */ - max3107_dowork(s); -} - -/* Function for returning control pin states */ -static unsigned int max3107_get_mctrl(struct uart_port *port) -{ - /* DCD and DSR are not wired and CTS/RTS is handled automatically - * so just indicate DSR and CAR asserted - */ - return TIOCM_DSR | TIOCM_CAR; -} - -/* Function for setting control pin states */ -static void max3107_set_mctrl(struct uart_port *port, unsigned int mctrl) -{ - /* DCD and DSR are not wired and CTS/RTS is hadnled automatically - * so do nothing - */ -} - -/* Function for configuring UART parameters */ -static void max3107_set_termios(struct uart_port *port, - struct ktermios *termios, - struct ktermios *old) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - struct tty_struct *tty; - int baud; - u16 new_lcr = 0; - u32 new_brg = 0; - unsigned long flags; - - if (!port->state) - return; - - tty = port->state->port.tty; - if (!tty) - return; - - /* Get new LCR register values */ - /* Word size */ - if ((termios->c_cflag & CSIZE) == CS7) - new_lcr |= MAX3107_LCR_WORD_LEN_7; - else - new_lcr |= MAX3107_LCR_WORD_LEN_8; - - /* Parity */ - if (termios->c_cflag & PARENB) { - new_lcr |= MAX3107_LCR_PARITY_BIT; - if (!(termios->c_cflag & PARODD)) - new_lcr |= MAX3107_LCR_EVENPARITY_BIT; - } - - /* Stop bits */ - if (termios->c_cflag & CSTOPB) { - /* 2 stop bits */ - new_lcr |= MAX3107_LCR_STOPLEN_BIT; - } - - /* Mask termios capabilities we don't support */ - termios->c_cflag &= ~CMSPAR; - - /* Set status ignore mask */ - s->port.ignore_status_mask = 0; - if (termios->c_iflag & IGNPAR) - s->port.ignore_status_mask |= MAX3107_ALL_ERRORS; - - /* Set low latency to immediately handle pushed data */ - s->port.state->port.tty->low_latency = 1; - - /* Get new baud rate generator configuration */ - baud = tty_get_baud_rate(tty); - - spin_lock_irqsave(&s->data_lock, flags); - new_brg = get_new_brg(baud, s); - /* if can't find the corrent config, use previous */ - if (!new_brg) { - baud = s->baud; - new_brg = s->brg_cfg; - } - spin_unlock_irqrestore(&s->data_lock, flags); - tty_termios_encode_baud_rate(termios, baud, baud); - s->baud = baud; - - /* Update timeout according to new baud rate */ - uart_update_timeout(port, termios->c_cflag, baud); - - spin_lock_irqsave(&s->data_lock, flags); - if (s->lcr_reg != new_lcr) { - s->lcr_reg = new_lcr; - s->lcr_commit = 1; - } - if (s->brg_cfg != new_brg) { - s->brg_cfg = new_brg; - s->brg_commit = 1; - } - spin_unlock_irqrestore(&s->data_lock, flags); - - /* Trigger work thread for doing the actual configuration change */ - max3107_dowork(s); -} - -/* Port shutdown function */ -static void max3107_shutdown(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - - if (s->suspended && s->pdata->hw_suspend) - s->pdata->hw_suspend(s, 0); - - /* Free the interrupt */ - free_irq(s->spi->irq, s); - - if (s->workqueue) { - /* Flush and destroy work queue */ - flush_workqueue(s->workqueue); - destroy_workqueue(s->workqueue); - s->workqueue = NULL; - } - - /* Suspend HW */ - if (s->pdata->hw_suspend) - s->pdata->hw_suspend(s, 1); -} - -/* Port startup function */ -static int max3107_startup(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - - /* Initialize work queue */ - s->workqueue = create_freezable_workqueue("max3107"); - if (!s->workqueue) { - dev_err(&s->spi->dev, "Workqueue creation failed\n"); - return -EBUSY; - } - INIT_WORK(&s->work, max3107_work); - - /* Setup IRQ */ - if (request_irq(s->spi->irq, max3107_irq, IRQF_TRIGGER_FALLING, - "max3107", s)) { - dev_err(&s->spi->dev, "IRQ reguest failed\n"); - destroy_workqueue(s->workqueue); - s->workqueue = NULL; - return -EBUSY; - } - - /* Resume HW */ - if (s->pdata->hw_suspend) - s->pdata->hw_suspend(s, 0); - - /* Init registers */ - max3107_register_init(s); - - return 0; -} - -/* Port type function */ -static const char *max3107_type(struct uart_port *port) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - return s->spi->modalias; -} - -/* Port release function */ -static void max3107_release_port(struct uart_port *port) -{ - /* Do nothing */ -} - -/* Port request function */ -static int max3107_request_port(struct uart_port *port) -{ - /* Do nothing */ - return 0; -} - -/* Port config function */ -static void max3107_config_port(struct uart_port *port, int flags) -{ - struct max3107_port *s = container_of(port, struct max3107_port, port); - s->port.type = PORT_MAX3107; -} - -/* Port verify function */ -static int max3107_verify_port(struct uart_port *port, - struct serial_struct *ser) -{ - if (ser->type == PORT_UNKNOWN || ser->type == PORT_MAX3107) - return 0; - - return -EINVAL; -} - -/* Port stop TX function */ -static void max3107_stop_tx(struct uart_port *port) -{ - /* Do nothing */ -} - -/* Port break control function */ -static void max3107_break_ctl(struct uart_port *port, int break_state) -{ - /* We don't support break control, do nothing */ -} - - -/* Port functions */ -static struct uart_ops max3107_ops = { - .tx_empty = max3107_tx_empty, - .set_mctrl = max3107_set_mctrl, - .get_mctrl = max3107_get_mctrl, - .stop_tx = max3107_stop_tx, - .start_tx = max3107_start_tx, - .stop_rx = max3107_stop_rx, - .enable_ms = max3107_enable_ms, - .break_ctl = max3107_break_ctl, - .startup = max3107_startup, - .shutdown = max3107_shutdown, - .set_termios = max3107_set_termios, - .type = max3107_type, - .release_port = max3107_release_port, - .request_port = max3107_request_port, - .config_port = max3107_config_port, - .verify_port = max3107_verify_port, -}; - -/* UART driver data */ -static struct uart_driver max3107_uart_driver = { - .owner = THIS_MODULE, - .driver_name = "ttyMAX", - .dev_name = "ttyMAX", - .nr = 1, -}; - -static int driver_registered = 0; - - - -/* 'Generic' platform data */ -static struct max3107_plat generic_plat_data = { - .loopback = 0, - .ext_clk = 1, - .hw_suspend = max3107_hw_susp, - .polled_mode = 0, - .poll_time = 0, -}; - - -/*******************************************************************/ - -/** - * max3107_probe - SPI bus probe entry point - * @spi: the spi device - * - * SPI wants us to probe this device and if appropriate claim it. - * Perform any platform specific requirements and then initialise - * the device. - */ - -int max3107_probe(struct spi_device *spi, struct max3107_plat *pdata) -{ - struct max3107_port *s; - u16 buf[2]; /* Buffer for SPI transfers */ - int retval; - - pr_info("enter max3107 probe\n"); - - /* Allocate port structure */ - s = kzalloc(sizeof(*s), GFP_KERNEL); - if (!s) { - pr_err("Allocating port structure failed\n"); - return -ENOMEM; - } - - s->pdata = pdata; - - /* SPI Rx buffer - * +2 for RX FIFO interrupt - * disabling and RX level query - */ - s->rxbuf = kzalloc(sizeof(u16) * (MAX3107_RX_FIFO_SIZE+2), GFP_KERNEL); - if (!s->rxbuf) { - pr_err("Allocating RX buffer failed\n"); - retval = -ENOMEM; - goto err_free4; - } - s->rxstr = kzalloc(sizeof(u8) * MAX3107_RX_FIFO_SIZE, GFP_KERNEL); - if (!s->rxstr) { - pr_err("Allocating RX buffer failed\n"); - retval = -ENOMEM; - goto err_free3; - } - /* SPI Tx buffer - * SPI transfer buffer - * +3 for TX FIFO empty - * interrupt disabling and - * enabling and TX enabling - */ - s->txbuf = kzalloc(sizeof(u16) * MAX3107_TX_FIFO_SIZE + 3, GFP_KERNEL); - if (!s->txbuf) { - pr_err("Allocating TX buffer failed\n"); - retval = -ENOMEM; - goto err_free2; - } - /* Initialize shared data lock */ - spin_lock_init(&s->data_lock); - - /* SPI intializations */ - dev_set_drvdata(&spi->dev, s); - spi->mode = SPI_MODE_0; - spi->dev.platform_data = pdata; - spi->bits_per_word = 16; - s->ext_clk = pdata->ext_clk; - s->loopback = pdata->loopback; - spi_setup(spi); - s->spi = spi; - - /* Check REV ID to ensure we are talking to what we expect */ - buf[0] = MAX3107_REVID_REG; - if (max3107_rw(s, (u8 *)buf, (u8 *)buf, 2)) { - dev_err(&s->spi->dev, "SPI transfer for REVID read failed\n"); - retval = -EIO; - goto err_free1; - } - if ((buf[0] & MAX3107_SPI_RX_DATA_MASK) != MAX3107_REVID1 && - (buf[0] & MAX3107_SPI_RX_DATA_MASK) != MAX3107_REVID2) { - dev_err(&s->spi->dev, "REVID %x does not match\n", - (buf[0] & MAX3107_SPI_RX_DATA_MASK)); - retval = -ENODEV; - goto err_free1; - } - - /* Disable all interrupts */ - buf[0] = (MAX3107_WRITE_BIT | MAX3107_IRQEN_REG | 0x0000); - buf[0] |= 0x0000; - - /* Configure clock source */ - buf[1] = (MAX3107_WRITE_BIT | MAX3107_CLKSRC_REG); - if (s->ext_clk) { - /* External clock */ - buf[1] |= MAX3107_CLKSRC_EXTCLK_BIT; - } - - /* PLL bypass ON */ - buf[1] |= MAX3107_CLKSRC_PLLBYP_BIT; - - /* Perform SPI transfer */ - if (max3107_rw(s, (u8 *)buf, NULL, 4)) { - dev_err(&s->spi->dev, "SPI transfer for init failed\n"); - retval = -EIO; - goto err_free1; - } - - /* Register UART driver */ - if (!driver_registered) { - retval = uart_register_driver(&max3107_uart_driver); - if (retval) { - dev_err(&s->spi->dev, "Registering UART driver failed\n"); - goto err_free1; - } - driver_registered = 1; - } - - /* Initialize UART port data */ - s->port.fifosize = 128; - s->port.ops = &max3107_ops; - s->port.line = 0; - s->port.dev = &spi->dev; - s->port.uartclk = 9600; - s->port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF; - s->port.irq = s->spi->irq; - s->port.type = PORT_MAX3107; - - /* Add UART port */ - retval = uart_add_one_port(&max3107_uart_driver, &s->port); - if (retval < 0) { - dev_err(&s->spi->dev, "Adding UART port failed\n"); - goto err_free1; - } - - if (pdata->configure) { - retval = pdata->configure(s); - if (retval < 0) - goto err_free1; - } - - /* Go to suspend mode */ - if (pdata->hw_suspend) - pdata->hw_suspend(s, 1); - - return 0; - -err_free1: - kfree(s->txbuf); -err_free2: - kfree(s->rxstr); -err_free3: - kfree(s->rxbuf); -err_free4: - kfree(s); - return retval; -} -EXPORT_SYMBOL_GPL(max3107_probe); - -/* Driver remove function */ -int max3107_remove(struct spi_device *spi) -{ - struct max3107_port *s = dev_get_drvdata(&spi->dev); - - pr_info("enter max3107 remove\n"); - - /* Remove port */ - if (uart_remove_one_port(&max3107_uart_driver, &s->port)) - dev_warn(&s->spi->dev, "Removing UART port failed\n"); - - - /* Free TxRx buffer */ - kfree(s->rxbuf); - kfree(s->rxstr); - kfree(s->txbuf); - - /* Free port structure */ - kfree(s); - - return 0; -} -EXPORT_SYMBOL_GPL(max3107_remove); - -/* Driver suspend function */ -int max3107_suspend(struct spi_device *spi, pm_message_t state) -{ -#ifdef CONFIG_PM - struct max3107_port *s = dev_get_drvdata(&spi->dev); - - pr_debug("enter suspend\n"); - - /* Suspend UART port */ - uart_suspend_port(&max3107_uart_driver, &s->port); - - /* Go to suspend mode */ - if (s->pdata->hw_suspend) - s->pdata->hw_suspend(s, 1); -#endif /* CONFIG_PM */ - return 0; -} -EXPORT_SYMBOL_GPL(max3107_suspend); - -/* Driver resume function */ -int max3107_resume(struct spi_device *spi) -{ -#ifdef CONFIG_PM - struct max3107_port *s = dev_get_drvdata(&spi->dev); - - pr_debug("enter resume\n"); - - /* Resume from suspend */ - if (s->pdata->hw_suspend) - s->pdata->hw_suspend(s, 0); - - /* Resume UART port */ - uart_resume_port(&max3107_uart_driver, &s->port); -#endif /* CONFIG_PM */ - return 0; -} -EXPORT_SYMBOL_GPL(max3107_resume); - -static int max3107_probe_generic(struct spi_device *spi) -{ - return max3107_probe(spi, &generic_plat_data); -} - -/* Spi driver data */ -static struct spi_driver max3107_driver = { - .driver = { - .name = "max3107", - .owner = THIS_MODULE, - }, - .probe = max3107_probe_generic, - .remove = __devexit_p(max3107_remove), - .suspend = max3107_suspend, - .resume = max3107_resume, -}; - -/* Driver init function */ -static int __init max3107_init(void) -{ - pr_info("enter max3107 init\n"); - return spi_register_driver(&max3107_driver); -} - -/* Driver exit function */ -static void __exit max3107_exit(void) -{ - pr_info("enter max3107 exit\n"); - /* Unregister UART driver */ - if (driver_registered) - uart_unregister_driver(&max3107_uart_driver); - spi_unregister_driver(&max3107_driver); -} - -module_init(max3107_init); -module_exit(max3107_exit); - -MODULE_DESCRIPTION("MAX3107 driver"); -MODULE_AUTHOR("Aavamobile"); -MODULE_ALIAS("spi:max3107"); -MODULE_LICENSE("GPL v2"); |