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authorAlexander Shiyan <shc_work@mail.ru>2012-08-06 19:42:32 +0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-08-16 23:12:25 +0400
commitf65444187a66bf54af32a10902877dd0326456d1 (patch)
tree9458139d0c7dd538d68cf6fa02e5ad4542162d83 /drivers/tty/serial/max3107.c
parent9574f36fb801035f6ab0fbb1b53ce2c12c17d100 (diff)
downloadlinux-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.c1215
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 17c7ba805d98..000000000000
--- 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");