From 010d442c4a295a73e90e93c5e42579cee61c5cc7 Mon Sep 17 00:00:00 2001 From: Komal Shah Date: Sun, 13 Aug 2006 23:44:09 +0200 Subject: [PATCH] i2c: New bus driver for TI OMAP boards i2c: New bus driver for TI OMAP boards This patch adds I2C bus driver for various Texas Instruments (TI) OMAP1/2 (http://www.ti.com/omap) series based boards like OMAP1510/1610/1710/242x. Signed-off-by: Komal Shah Signed-off-by: Jean Delvare Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/Kconfig | 10 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-omap.c | 676 ++++++++++++++++++++++++++++++++++ 3 files changed, 687 insertions(+) create mode 100644 drivers/i2c/busses/i2c-omap.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 404508ca7326..1df3bd97cb15 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -287,6 +287,16 @@ config I2C_OCORES This driver can also be built as a module. If so, the module will be called i2c-ocores. +config I2C_OMAP + tristate "OMAP I2C adapter" + depends on I2C && ARCH_OMAP + default y if MACH_OMAP_H3 || MACH_OMAP_OSK + help + If you say yes to this option, support will be included for the + I2C interface on the Texas Instruments OMAP1/2 family of processors. + Like OMAP1510/1610/1710/5912 and OMAP242x. + For details see http://www.ti.com/omap. + config I2C_PARPORT tristate "Parallel port adapter" depends on I2C && PARPORT diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index ac56df53155b..493c87289b62 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -24,6 +24,7 @@ obj-$(CONFIG_I2C_MPC) += i2c-mpc.o obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o obj-$(CONFIG_I2C_NFORCE2) += i2c-nforce2.o obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o +obj-$(CONFIG_I2C_OMAP) += i2c-omap.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c new file mode 100644 index 000000000000..a129af991388 --- /dev/null +++ b/drivers/i2c/busses/i2c-omap.c @@ -0,0 +1,676 @@ +/* + * TI OMAP I2C master mode driver + * + * Copyright (C) 2003 MontaVista Software, Inc. + * Copyright (C) 2004 Texas Instruments. + * + * Updated to work with multiple I2C interfaces on 24xx by + * Tony Lindgren and Imre Deak + * Copyright (C) 2005 Nokia Corporation + * + * Cleaned up by Juha Yrjölä + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* timeout waiting for the controller to respond */ +#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) + +#define OMAP_I2C_REV_REG 0x00 +#define OMAP_I2C_IE_REG 0x04 +#define OMAP_I2C_STAT_REG 0x08 +#define OMAP_I2C_IV_REG 0x0c +#define OMAP_I2C_SYSS_REG 0x10 +#define OMAP_I2C_BUF_REG 0x14 +#define OMAP_I2C_CNT_REG 0x18 +#define OMAP_I2C_DATA_REG 0x1c +#define OMAP_I2C_SYSC_REG 0x20 +#define OMAP_I2C_CON_REG 0x24 +#define OMAP_I2C_OA_REG 0x28 +#define OMAP_I2C_SA_REG 0x2c +#define OMAP_I2C_PSC_REG 0x30 +#define OMAP_I2C_SCLL_REG 0x34 +#define OMAP_I2C_SCLH_REG 0x38 +#define OMAP_I2C_SYSTEST_REG 0x3c + +/* I2C Interrupt Enable Register (OMAP_I2C_IE): */ +#define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */ +#define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */ +#define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */ +#define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */ +#define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */ + +/* I2C Status Register (OMAP_I2C_STAT): */ +#define OMAP_I2C_STAT_SBD (1 << 15) /* Single byte data */ +#define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */ +#define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */ +#define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */ +#define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */ +#define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */ +#define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */ +#define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */ +#define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */ +#define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */ +#define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */ + +/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */ +#define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */ +#define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */ + +/* I2C Configuration Register (OMAP_I2C_CON): */ +#define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */ +#define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */ +#define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */ +#define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */ +#define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */ +#define OMAP_I2C_CON_XA (1 << 8) /* Expand address */ +#define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */ +#define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */ +#define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */ + +/* I2C System Test Register (OMAP_I2C_SYSTEST): */ +#ifdef DEBUG +#define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */ +#define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */ +#define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */ +#define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */ +#define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */ +#define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */ +#define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */ +#define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */ +#endif + +/* I2C System Status register (OMAP_I2C_SYSS): */ +#define OMAP_I2C_SYSS_RDONE (1 << 0) /* Reset Done */ + +/* I2C System Configuration Register (OMAP_I2C_SYSC): */ +#define OMAP_I2C_SYSC_SRST (1 << 1) /* Soft Reset */ + +/* REVISIT: Use platform_data instead of module parameters */ +/* Fast Mode = 400 kHz, Standard = 100 kHz */ +static int clock = 100; /* Default: 100 kHz */ +module_param(clock, int, 0); +MODULE_PARM_DESC(clock, "Set I2C clock in kHz: 400=fast mode (default == 100)"); + +struct omap_i2c_dev { + struct device *dev; + void __iomem *base; /* virtual */ + int irq; + struct clk *iclk; /* Interface clock */ + struct clk *fclk; /* Functional clock */ + struct completion cmd_complete; + struct resource *ioarea; + u16 cmd_err; + u8 *buf; + size_t buf_len; + struct i2c_adapter adapter; + unsigned rev1:1; +}; + +static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev, + int reg, u16 val) +{ + __raw_writew(val, i2c_dev->base + reg); +} + +static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg) +{ + return __raw_readw(i2c_dev->base + reg); +} + +static int omap_i2c_get_clocks(struct omap_i2c_dev *dev) +{ + if (cpu_is_omap16xx() || cpu_is_omap24xx()) { + dev->iclk = clk_get(dev->dev, "i2c_ick"); + if (IS_ERR(dev->iclk)) { + dev->iclk = NULL; + return -ENODEV; + } + } + + dev->fclk = clk_get(dev->dev, "i2c_fck"); + if (IS_ERR(dev->fclk)) { + if (dev->iclk != NULL) { + clk_put(dev->iclk); + dev->iclk = NULL; + } + dev->fclk = NULL; + return -ENODEV; + } + + return 0; +} + +static void omap_i2c_put_clocks(struct omap_i2c_dev *dev) +{ + clk_put(dev->fclk); + dev->fclk = NULL; + if (dev->iclk != NULL) { + clk_put(dev->iclk); + dev->iclk = NULL; + } +} + +static void omap_i2c_enable_clocks(struct omap_i2c_dev *dev) +{ + if (dev->iclk != NULL) + clk_enable(dev->iclk); + clk_enable(dev->fclk); +} + +static void omap_i2c_disable_clocks(struct omap_i2c_dev *dev) +{ + if (dev->iclk != NULL) + clk_disable(dev->iclk); + clk_disable(dev->fclk); +} + +static int omap_i2c_init(struct omap_i2c_dev *dev) +{ + u16 psc = 0; + unsigned long fclk_rate = 12000000; + unsigned long timeout; + + if (!dev->rev1) { + omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, OMAP_I2C_SYSC_SRST); + /* For some reason we need to set the EN bit before the + * reset done bit gets set. */ + timeout = jiffies + OMAP_I2C_TIMEOUT; + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) & + OMAP_I2C_SYSS_RDONE)) { + if (time_after(jiffies, timeout)) { + dev_warn(dev->dev, "timeout waiting" + "for controller reset\n"); + return -ETIMEDOUT; + } + msleep(1); + } + } + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); + + if (cpu_class_is_omap1()) { + struct clk *armxor_ck; + + armxor_ck = clk_get(NULL, "armxor_ck"); + if (IS_ERR(armxor_ck)) + dev_warn(dev->dev, "Could not get armxor_ck\n"); + else { + fclk_rate = clk_get_rate(armxor_ck); + clk_put(armxor_ck); + } + /* TRM for 5912 says the I2C clock must be prescaled to be + * between 7 - 12 MHz. The XOR input clock is typically + * 12, 13 or 19.2 MHz. So we should have code that produces: + * + * XOR MHz Divider Prescaler + * 12 1 0 + * 13 2 1 + * 19.2 2 1 + */ + if (fclk_rate > 16000000) + psc = (fclk_rate + 8000000) / 12000000; + } + + /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */ + omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc); + + /* Program desired operating rate */ + fclk_rate /= (psc + 1) * 1000; + if (psc > 2) + psc = 2; + + omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, + fclk_rate / (clock * 2) - 7 + psc); + omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, + fclk_rate / (clock * 2) - 7 + psc); + + /* Take the I2C module out of reset: */ + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + + /* Enable interrupts */ + omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, + (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY | + OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK | + OMAP_I2C_IE_AL)); + return 0; +} + +/* + * Waiting on Bus Busy + */ +static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev) +{ + unsigned long timeout; + + timeout = jiffies + OMAP_I2C_TIMEOUT; + while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) { + if (time_after(jiffies, timeout)) { + dev_warn(dev->dev, "timeout waiting for bus ready\n"); + return -ETIMEDOUT; + } + msleep(1); + } + + return 0; +} + +/* + * Low level master read/write transaction. + */ +static int omap_i2c_xfer_msg(struct i2c_adapter *adap, + struct i2c_msg *msg, int stop) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + int r; + u16 w; + + dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", + msg->addr, msg->len, msg->flags, stop); + + if (msg->len == 0) + return -EINVAL; + + omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr); + + /* REVISIT: Could the STB bit of I2C_CON be used with probing? */ + dev->buf = msg->buf; + dev->buf_len = msg->len; + + omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len); + + init_completion(&dev->cmd_complete); + dev->cmd_err = 0; + + w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT; + if (msg->flags & I2C_M_TEN) + w |= OMAP_I2C_CON_XA; + if (!(msg->flags & I2C_M_RD)) + w |= OMAP_I2C_CON_TRX; + if (stop) + w |= OMAP_I2C_CON_STP; + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w); + + r = wait_for_completion_interruptible_timeout(&dev->cmd_complete, + OMAP_I2C_TIMEOUT); + dev->buf_len = 0; + if (r < 0) + return r; + if (r == 0) { + dev_err(dev->dev, "controller timed out\n"); + omap_i2c_init(dev); + return -ETIMEDOUT; + } + + if (likely(!dev->cmd_err)) + return 0; + + /* We have an error */ + if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR | + OMAP_I2C_STAT_XUDF)) { + omap_i2c_init(dev); + return -EIO; + } + + if (dev->cmd_err & OMAP_I2C_STAT_NACK) { + if (msg->flags & I2C_M_IGNORE_NAK) + return 0; + if (stop) { + w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG); + w |= OMAP_I2C_CON_STP; + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w); + } + return -EREMOTEIO; + } + return -EIO; +} + + +/* + * Prepare controller for a transaction and call omap_i2c_xfer_msg + * to do the work during IRQ processing. + */ +static int +omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); + int i; + int r; + + omap_i2c_enable_clocks(dev); + + /* REVISIT: initialize and use adap->retries. This is an optional + * feature */ + if ((r = omap_i2c_wait_for_bb(dev)) < 0) + goto out; + + for (i = 0; i < num; i++) { + r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1))); + if (r != 0) + break; + } + + if (r == 0) + r = num; +out: + omap_i2c_disable_clocks(dev); + return r; +} + +static u32 +omap_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); +} + +static inline void +omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err) +{ + dev->cmd_err |= err; + complete(&dev->cmd_complete); +} + +static inline void +omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat) +{ + omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat); +} + +static irqreturn_t +omap_i2c_rev1_isr(int this_irq, void *dev_id, struct pt_regs *regs) +{ + struct omap_i2c_dev *dev = dev_id; + u16 iv, w; + + iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); + switch (iv) { + case 0x00: /* None */ + break; + case 0x01: /* Arbitration lost */ + dev_err(dev->dev, "Arbitration lost\n"); + omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL); + break; + case 0x02: /* No acknowledgement */ + omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK); + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP); + break; + case 0x03: /* Register access ready */ + omap_i2c_complete_cmd(dev, 0); + break; + case 0x04: /* Receive data ready */ + if (dev->buf_len) { + w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG); + *dev->buf++ = w; + dev->buf_len--; + if (dev->buf_len) { + *dev->buf++ = w >> 8; + dev->buf_len--; + } + } else + dev_err(dev->dev, "RRDY IRQ while no data requested\n"); + break; + case 0x05: /* Transmit data ready */ + if (dev->buf_len) { + w = *dev->buf++; + dev->buf_len--; + if (dev->buf_len) { + w |= *dev->buf++ << 8; + dev->buf_len--; + } + omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); + } else + dev_err(dev->dev, "XRDY IRQ while no data to send\n"); + break; + default: + return IRQ_NONE; + } + + return IRQ_HANDLED; +} + +static irqreturn_t +omap_i2c_isr(int this_irq, void *dev_id, struct pt_regs *regs) +{ + struct omap_i2c_dev *dev = dev_id; + u16 bits; + u16 stat, w; + int count = 0; + + bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); + while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) { + dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat); + if (count++ == 100) { + dev_warn(dev->dev, "Too much work in one IRQ\n"); + break; + } + + omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat); + + if (stat & OMAP_I2C_STAT_ARDY) { + omap_i2c_complete_cmd(dev, 0); + continue; + } + if (stat & OMAP_I2C_STAT_RRDY) { + w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG); + if (dev->buf_len) { + *dev->buf++ = w; + dev->buf_len--; + if (dev->buf_len) { + *dev->buf++ = w >> 8; + dev->buf_len--; + } + } else + dev_err(dev->dev, "RRDY IRQ while no data" + "requested\n"); + omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY); + continue; + } + if (stat & OMAP_I2C_STAT_XRDY) { + w = 0; + if (dev->buf_len) { + w = *dev->buf++; + dev->buf_len--; + if (dev->buf_len) { + w |= *dev->buf++ << 8; + dev->buf_len--; + } + } else + dev_err(dev->dev, "XRDY IRQ while no" + "data to send\n"); + omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); + omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY); + continue; + } + if (stat & OMAP_I2C_STAT_ROVR) { + dev_err(dev->dev, "Receive overrun\n"); + dev->cmd_err |= OMAP_I2C_STAT_ROVR; + } + if (stat & OMAP_I2C_STAT_XUDF) { + dev_err(dev->dev, "Transmit overflow\n"); + dev->cmd_err |= OMAP_I2C_STAT_XUDF; + } + if (stat & OMAP_I2C_STAT_NACK) { + omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK); + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, + OMAP_I2C_CON_STP); + } + if (stat & OMAP_I2C_STAT_AL) { + dev_err(dev->dev, "Arbitration lost\n"); + omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL); + } + } + + return count ? IRQ_HANDLED : IRQ_NONE; +} + +static struct i2c_algorithm omap_i2c_algo = { + .master_xfer = omap_i2c_xfer, + .functionality = omap_i2c_func, +}; + +static int +omap_i2c_probe(struct platform_device *pdev) +{ + struct omap_i2c_dev *dev; + struct i2c_adapter *adap; + struct resource *mem, *irq, *ioarea; + int r; + + /* NOTE: driver uses the static register mapping */ + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mem) { + dev_err(&pdev->dev, "no mem resource?\n"); + return -ENODEV; + } + irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!irq) { + dev_err(&pdev->dev, "no irq resource?\n"); + return -ENODEV; + } + + ioarea = request_mem_region(mem->start, (mem->end - mem->start) + 1, + pdev->name); + if (!ioarea) { + dev_err(&pdev->dev, "I2C region already claimed\n"); + return -EBUSY; + } + + if (clock > 200) + clock = 400; /* Fast mode */ + else + clock = 100; /* Standard mode */ + + dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL); + if (!dev) { + r = -ENOMEM; + goto err_release_region; + } + + dev->dev = &pdev->dev; + dev->irq = irq->start; + dev->base = (void __iomem *) IO_ADDRESS(mem->start); + platform_set_drvdata(pdev, dev); + + if ((r = omap_i2c_get_clocks(dev)) != 0) + goto err_free_mem; + + omap_i2c_enable_clocks(dev); + + if (cpu_is_omap15xx()) + dev->rev1 = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) < 0x20; + + /* reset ASAP, clearing any IRQs */ + omap_i2c_init(dev); + + r = request_irq(dev->irq, dev->rev1 ? omap_i2c_rev1_isr : omap_i2c_isr, + 0, pdev->name, dev); + + if (r) { + dev_err(dev->dev, "failure requesting irq %i\n", dev->irq); + goto err_unuse_clocks; + } + r = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff; + dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", + pdev->id, r >> 4, r & 0xf, clock); + + adap = &dev->adapter; + i2c_set_adapdata(adap, dev); + adap->owner = THIS_MODULE; + adap->class = I2C_CLASS_HWMON; + strncpy(adap->name, "OMAP I2C adapter", sizeof(adap->name)); + adap->algo = &omap_i2c_algo; + adap->dev.parent = &pdev->dev; + + /* i2c device drivers may be active on return from add_adapter() */ + r = i2c_add_adapter(adap); + if (r) { + dev_err(dev->dev, "failure adding adapter\n"); + goto err_free_irq; + } + + omap_i2c_disable_clocks(dev); + + return 0; + +err_free_irq: + free_irq(dev->irq, dev); +err_unuse_clocks: + omap_i2c_disable_clocks(dev); + omap_i2c_put_clocks(dev); +err_free_mem: + platform_set_drvdata(pdev, NULL); + kfree(dev); +err_release_region: + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); + release_mem_region(mem->start, (mem->end - mem->start) + 1); + + return r; +} + +static int +omap_i2c_remove(struct platform_device *pdev) +{ + struct omap_i2c_dev *dev = platform_get_drvdata(pdev); + struct resource *mem; + + platform_set_drvdata(pdev, NULL); + + free_irq(dev->irq, dev); + i2c_del_adapter(&dev->adapter); + omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); + omap_i2c_put_clocks(dev); + kfree(dev); + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mem->start, (mem->end - mem->start) + 1); + return 0; +} + +static struct platform_driver omap_i2c_driver = { + .probe = omap_i2c_probe, + .remove = omap_i2c_remove, + .driver = { + .name = "i2c_omap", + .owner = THIS_MODULE, + }, +}; + +/* I2C may be needed to bring up other drivers */ +static int __init +omap_i2c_init_driver(void) +{ + return platform_driver_register(&omap_i2c_driver); +} +subsys_initcall(omap_i2c_init_driver); + +static void __exit omap_i2c_exit_driver(void) +{ + platform_driver_unregister(&omap_i2c_driver); +} +module_exit(omap_i2c_exit_driver); + +MODULE_AUTHOR("MontaVista Software, Inc. (and others)"); +MODULE_DESCRIPTION("TI OMAP I2C bus adapter"); +MODULE_LICENSE("GPL"); -- 2.20.1