summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/Kconfig10
-rw-r--r--drivers/i2c/busses/Makefile1
-rw-r--r--drivers/i2c/busses/i2c-omap.c676
3 files changed, 687 insertions, 0 deletions
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 <tony@atomide.com> and Imre Deak <imre.deak@nokia.com>
+ * Copyright (C) 2005 Nokia Corporation
+ *
+ * Cleaned up by Juha Yrjölä <juha.yrjola@nokia.com>
+ *
+ * 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 <linux/module.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#include <asm/io.h>
+
+/* 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");
OpenPOWER on IntegriCloud