i2c: New PMC MSP71xx TWI bus driver
Add TWI driver for the PMC-Sierra MSP71xx devices.
[JD: Drop the probe hack, don't set algo_data as we never use it, return
the right error code if the driver registration fails.]
Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/busses/i2c-pmcmsp.c b/drivers/i2c/busses/i2c-pmcmsp.c
new file mode 100644
index 0000000..03188d2
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pmcmsp.c
@@ -0,0 +1,653 @@
+/*
+ * Specific bus support for PMC-TWI compliant implementation on MSP71xx.
+ *
+ * Copyright 2005-2007 PMC-Sierra, Inc.
+ *
+ * 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 SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
+ * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+#define DRV_NAME "pmcmsptwi"
+
+#define MSP_TWI_SF_CLK_REG_OFFSET 0x00
+#define MSP_TWI_HS_CLK_REG_OFFSET 0x04
+#define MSP_TWI_CFG_REG_OFFSET 0x08
+#define MSP_TWI_CMD_REG_OFFSET 0x0c
+#define MSP_TWI_ADD_REG_OFFSET 0x10
+#define MSP_TWI_DAT_0_REG_OFFSET 0x14
+#define MSP_TWI_DAT_1_REG_OFFSET 0x18
+#define MSP_TWI_INT_STS_REG_OFFSET 0x1c
+#define MSP_TWI_INT_MSK_REG_OFFSET 0x20
+#define MSP_TWI_BUSY_REG_OFFSET 0x24
+
+#define MSP_TWI_INT_STS_DONE (1 << 0)
+#define MSP_TWI_INT_STS_LOST_ARBITRATION (1 << 1)
+#define MSP_TWI_INT_STS_NO_RESPONSE (1 << 2)
+#define MSP_TWI_INT_STS_DATA_COLLISION (1 << 3)
+#define MSP_TWI_INT_STS_BUSY (1 << 4)
+#define MSP_TWI_INT_STS_ALL 0x1f
+
+#define MSP_MAX_BYTES_PER_RW 8
+#define MSP_MAX_POLL 5
+#define MSP_POLL_DELAY 10
+#define MSP_IRQ_TIMEOUT (MSP_MAX_POLL * MSP_POLL_DELAY)
+
+/* IO Operation macros */
+#define pmcmsptwi_readl __raw_readl
+#define pmcmsptwi_writel __raw_writel
+
+/* TWI command type */
+enum pmcmsptwi_cmd_type {
+ MSP_TWI_CMD_WRITE = 0, /* Write only */
+ MSP_TWI_CMD_READ = 1, /* Read only */
+ MSP_TWI_CMD_WRITE_READ = 2, /* Write then Read */
+};
+
+/* The possible results of the xferCmd */
+enum pmcmsptwi_xfer_result {
+ MSP_TWI_XFER_OK = 0,
+ MSP_TWI_XFER_TIMEOUT,
+ MSP_TWI_XFER_BUSY,
+ MSP_TWI_XFER_DATA_COLLISION,
+ MSP_TWI_XFER_NO_RESPONSE,
+ MSP_TWI_XFER_LOST_ARBITRATION,
+};
+
+/* Corresponds to a PMCTWI clock configuration register */
+struct pmcmsptwi_clock {
+ u8 filter; /* Bits 15:12, default = 0x03 */
+ u16 clock; /* Bits 9:0, default = 0x001f */
+};
+
+struct pmcmsptwi_clockcfg {
+ struct pmcmsptwi_clock standard; /* The standard/fast clock config */
+ struct pmcmsptwi_clock highspeed; /* The highspeed clock config */
+};
+
+/* Corresponds to the main TWI configuration register */
+struct pmcmsptwi_cfg {
+ u8 arbf; /* Bits 15:12, default=0x03 */
+ u8 nak; /* Bits 11:8, default=0x03 */
+ u8 add10; /* Bit 7, default=0x00 */
+ u8 mst_code; /* Bits 6:4, default=0x00 */
+ u8 arb; /* Bit 1, default=0x01 */
+ u8 highspeed; /* Bit 0, default=0x00 */
+};
+
+/* A single pmctwi command to issue */
+struct pmcmsptwi_cmd {
+ u16 addr; /* The slave address (7 or 10 bits) */
+ enum pmcmsptwi_cmd_type type; /* The command type */
+ u8 write_len; /* Number of bytes in the write buffer */
+ u8 read_len; /* Number of bytes in the read buffer */
+ u8 *write_data; /* Buffer of characters to send */
+ u8 *read_data; /* Buffer to fill with incoming data */
+};
+
+/* The private data */
+struct pmcmsptwi_data {
+ void __iomem *iobase; /* iomapped base for IO */
+ int irq; /* IRQ to use (0 disables) */
+ struct completion wait; /* Completion for xfer */
+ struct mutex lock; /* Used for threadsafeness */
+ enum pmcmsptwi_xfer_result last_result; /* result of last xfer */
+};
+
+/* The default settings */
+const static struct pmcmsptwi_clockcfg pmcmsptwi_defclockcfg = {
+ .standard = {
+ .filter = 0x3,
+ .clock = 0x1f,
+ },
+ .highspeed = {
+ .filter = 0x3,
+ .clock = 0x1f,
+ },
+};
+
+const static struct pmcmsptwi_cfg pmcmsptwi_defcfg = {
+ .arbf = 0x03,
+ .nak = 0x03,
+ .add10 = 0x00,
+ .mst_code = 0x00,
+ .arb = 0x01,
+ .highspeed = 0x00,
+};
+
+static struct pmcmsptwi_data pmcmsptwi_data;
+
+static struct i2c_adapter pmcmsptwi_adapter;
+
+/* inline helper functions */
+static inline u32 pmcmsptwi_clock_to_reg(
+ const struct pmcmsptwi_clock *clock)
+{
+ return ((clock->filter & 0xf) << 12) | (clock->clock & 0x03ff);
+}
+
+static inline void pmcmsptwi_reg_to_clock(
+ u32 reg, struct pmcmsptwi_clock *clock)
+{
+ clock->filter = (reg >> 12) & 0xf;
+ clock->clock = reg & 0x03ff;
+}
+
+static inline u32 pmcmsptwi_cfg_to_reg(const struct pmcmsptwi_cfg *cfg)
+{
+ return ((cfg->arbf & 0xf) << 12) |
+ ((cfg->nak & 0xf) << 8) |
+ ((cfg->add10 & 0x1) << 7) |
+ ((cfg->mst_code & 0x7) << 4) |
+ ((cfg->arb & 0x1) << 1) |
+ (cfg->highspeed & 0x1);
+}
+
+static inline void pmcmsptwi_reg_to_cfg(u32 reg, struct pmcmsptwi_cfg *cfg)
+{
+ cfg->arbf = (reg >> 12) & 0xf;
+ cfg->nak = (reg >> 8) & 0xf;
+ cfg->add10 = (reg >> 7) & 0x1;
+ cfg->mst_code = (reg >> 4) & 0x7;
+ cfg->arb = (reg >> 1) & 0x1;
+ cfg->highspeed = reg & 0x1;
+}
+
+/*
+ * Sets the current clock configuration
+ */
+static void pmcmsptwi_set_clock_config(const struct pmcmsptwi_clockcfg *cfg,
+ struct pmcmsptwi_data *data)
+{
+ mutex_lock(&data->lock);
+ pmcmsptwi_writel(pmcmsptwi_clock_to_reg(&cfg->standard),
+ data->iobase + MSP_TWI_SF_CLK_REG_OFFSET);
+ pmcmsptwi_writel(pmcmsptwi_clock_to_reg(&cfg->highspeed),
+ data->iobase + MSP_TWI_HS_CLK_REG_OFFSET);
+ mutex_unlock(&data->lock);
+}
+
+/*
+ * Gets the current TWI bus configuration
+ */
+static void pmcmsptwi_get_twi_config(struct pmcmsptwi_cfg *cfg,
+ struct pmcmsptwi_data *data)
+{
+ mutex_lock(&data->lock);
+ pmcmsptwi_reg_to_cfg(pmcmsptwi_readl(
+ data->iobase + MSP_TWI_CFG_REG_OFFSET), cfg);
+ mutex_unlock(&data->lock);
+}
+
+/*
+ * Sets the current TWI bus configuration
+ */
+static void pmcmsptwi_set_twi_config(const struct pmcmsptwi_cfg *cfg,
+ struct pmcmsptwi_data *data)
+{
+ mutex_lock(&data->lock);
+ pmcmsptwi_writel(pmcmsptwi_cfg_to_reg(cfg),
+ data->iobase + MSP_TWI_CFG_REG_OFFSET);
+ mutex_unlock(&data->lock);
+}
+
+/*
+ * Parses the 'int_sts' register and returns a well-defined error code
+ */
+static enum pmcmsptwi_xfer_result pmcmsptwi_get_result(u32 reg)
+{
+ if (reg & MSP_TWI_INT_STS_LOST_ARBITRATION) {
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Result: Lost arbitration\n");
+ return MSP_TWI_XFER_LOST_ARBITRATION;
+ } else if (reg & MSP_TWI_INT_STS_NO_RESPONSE) {
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Result: No response\n");
+ return MSP_TWI_XFER_NO_RESPONSE;
+ } else if (reg & MSP_TWI_INT_STS_DATA_COLLISION) {
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Result: Data collision\n");
+ return MSP_TWI_XFER_DATA_COLLISION;
+ } else if (reg & MSP_TWI_INT_STS_BUSY) {
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Result: Bus busy\n");
+ return MSP_TWI_XFER_BUSY;
+ }
+
+ dev_dbg(&pmcmsptwi_adapter.dev, "Result: Operation succeeded\n");
+ return MSP_TWI_XFER_OK;
+}
+
+/*
+ * In interrupt mode, handle the interrupt.
+ * NOTE: Assumes data->lock is held.
+ */
+static irqreturn_t pmcmsptwi_interrupt(int irq, void *ptr)
+{
+ struct pmcmsptwi_data *data = ptr;
+
+ u32 reason = pmcmsptwi_readl(data->iobase +
+ MSP_TWI_INT_STS_REG_OFFSET);
+ pmcmsptwi_writel(reason, data->iobase + MSP_TWI_INT_STS_REG_OFFSET);
+
+ dev_dbg(&pmcmsptwi_adapter.dev, "Got interrupt 0x%08x\n", reason);
+ if (!(reason & MSP_TWI_INT_STS_DONE))
+ return IRQ_NONE;
+
+ data->last_result = pmcmsptwi_get_result(reason);
+ complete(&data->wait);
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Probe for and register the device and return 0 if there is one.
+ */
+static int __devinit pmcmsptwi_probe(struct platform_device *pldev)
+{
+ struct resource *res;
+ int rc = -ENODEV;
+
+ /* get the static platform resources */
+ res = platform_get_resource(pldev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pldev->dev, "IOMEM resource not found\n");
+ goto ret_err;
+ }
+
+ /* reserve the memory region */
+ if (!request_mem_region(res->start, res->end - res->start + 1,
+ pldev->name)) {
+ dev_err(&pldev->dev,
+ "Unable to get memory/io address region 0x%08x\n",
+ res->start);
+ rc = -EBUSY;
+ goto ret_err;
+ }
+
+ /* remap the memory */
+ pmcmsptwi_data.iobase = ioremap_nocache(res->start,
+ res->end - res->start + 1);
+ if (!pmcmsptwi_data.iobase) {
+ dev_err(&pldev->dev,
+ "Unable to ioremap address 0x%08x\n", res->start);
+ rc = -EIO;
+ goto ret_unreserve;
+ }
+
+ /* request the irq */
+ pmcmsptwi_data.irq = platform_get_irq(pldev, 0);
+ if (pmcmsptwi_data.irq) {
+ rc = request_irq(pmcmsptwi_data.irq, &pmcmsptwi_interrupt,
+ IRQF_SHARED | IRQF_DISABLED | IRQF_SAMPLE_RANDOM,
+ pldev->name, &pmcmsptwi_data);
+ if (rc == 0) {
+ /*
+ * Enable 'DONE' interrupt only.
+ *
+ * If you enable all interrupts, you will get one on
+ * error and another when the operation completes.
+ * This way you only have to handle one interrupt,
+ * but you can still check all result flags.
+ */
+ pmcmsptwi_writel(MSP_TWI_INT_STS_DONE,
+ pmcmsptwi_data.iobase +
+ MSP_TWI_INT_MSK_REG_OFFSET);
+ } else {
+ dev_warn(&pldev->dev,
+ "Could not assign TWI IRQ handler "
+ "to irq %d (continuing with poll)\n",
+ pmcmsptwi_data.irq);
+ pmcmsptwi_data.irq = 0;
+ }
+ }
+
+ init_completion(&pmcmsptwi_data.wait);
+ mutex_init(&pmcmsptwi_data.lock);
+
+ pmcmsptwi_set_clock_config(&pmcmsptwi_defclockcfg, &pmcmsptwi_data);
+ pmcmsptwi_set_twi_config(&pmcmsptwi_defcfg, &pmcmsptwi_data);
+
+ printk(KERN_INFO DRV_NAME ": Registering MSP71xx I2C adapter\n");
+
+ pmcmsptwi_adapter.dev.parent = &pldev->dev;
+ platform_set_drvdata(pldev, &pmcmsptwi_adapter);
+ i2c_set_adapdata(&pmcmsptwi_adapter, &pmcmsptwi_data);
+
+ rc = i2c_add_adapter(&pmcmsptwi_adapter);
+ if (rc) {
+ dev_err(&pldev->dev, "Unable to register I2C adapter\n");
+ goto ret_unmap;
+ }
+
+ return 0;
+
+ret_unmap:
+ platform_set_drvdata(pldev, NULL);
+ if (pmcmsptwi_data.irq) {
+ pmcmsptwi_writel(0,
+ pmcmsptwi_data.iobase + MSP_TWI_INT_MSK_REG_OFFSET);
+ free_irq(pmcmsptwi_data.irq, &pmcmsptwi_data);
+ }
+
+ iounmap(pmcmsptwi_data.iobase);
+
+ret_unreserve:
+ release_mem_region(res->start, res->end - res->start + 1);
+
+ret_err:
+ return rc;
+}
+
+/*
+ * Release the device and return 0 if there is one.
+ */
+static int __devexit pmcmsptwi_remove(struct platform_device *pldev)
+{
+ struct resource *res;
+
+ i2c_del_adapter(&pmcmsptwi_adapter);
+
+ platform_set_drvdata(pldev, NULL);
+ if (pmcmsptwi_data.irq) {
+ pmcmsptwi_writel(0,
+ pmcmsptwi_data.iobase + MSP_TWI_INT_MSK_REG_OFFSET);
+ free_irq(pmcmsptwi_data.irq, &pmcmsptwi_data);
+ }
+
+ iounmap(pmcmsptwi_data.iobase);
+
+ res = platform_get_resource(pldev, IORESOURCE_MEM, 0);
+ release_mem_region(res->start, res->end - res->start + 1);
+
+ return 0;
+}
+
+/*
+ * Polls the 'busy' register until the command is complete.
+ * NOTE: Assumes data->lock is held.
+ */
+static void pmcmsptwi_poll_complete(struct pmcmsptwi_data *data)
+{
+ int i;
+
+ for (i = 0; i < MSP_MAX_POLL; i++) {
+ u32 val = pmcmsptwi_readl(data->iobase +
+ MSP_TWI_BUSY_REG_OFFSET);
+ if (val == 0) {
+ u32 reason = pmcmsptwi_readl(data->iobase +
+ MSP_TWI_INT_STS_REG_OFFSET);
+ pmcmsptwi_writel(reason, data->iobase +
+ MSP_TWI_INT_STS_REG_OFFSET);
+ data->last_result = pmcmsptwi_get_result(reason);
+ return;
+ }
+ udelay(MSP_POLL_DELAY);
+ }
+
+ dev_dbg(&pmcmsptwi_adapter.dev, "Result: Poll timeout\n");
+ data->last_result = MSP_TWI_XFER_TIMEOUT;
+}
+
+/*
+ * Do the transfer (low level):
+ * May use interrupt-driven or polling, depending on if an IRQ is
+ * presently registered.
+ * NOTE: Assumes data->lock is held.
+ */
+static enum pmcmsptwi_xfer_result pmcmsptwi_do_xfer(
+ u32 reg, struct pmcmsptwi_data *data)
+{
+ dev_dbg(&pmcmsptwi_adapter.dev, "Writing cmd reg 0x%08x\n", reg);
+ pmcmsptwi_writel(reg, data->iobase + MSP_TWI_CMD_REG_OFFSET);
+ if (data->irq) {
+ unsigned long timeleft = wait_for_completion_timeout(
+ &data->wait, MSP_IRQ_TIMEOUT);
+ if (timeleft == 0) {
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Result: IRQ timeout\n");
+ complete(&data->wait);
+ data->last_result = MSP_TWI_XFER_TIMEOUT;
+ }
+ } else
+ pmcmsptwi_poll_complete(data);
+
+ return data->last_result;
+}
+
+/*
+ * Helper routine, converts 'pmctwi_cmd' struct to register format
+ */
+static inline u32 pmcmsptwi_cmd_to_reg(const struct pmcmsptwi_cmd *cmd)
+{
+ return ((cmd->type & 0x3) << 8) |
+ (((cmd->write_len - 1) & 0x7) << 4) |
+ ((cmd->read_len - 1) & 0x7);
+}
+
+/*
+ * Do the transfer (high level)
+ */
+static enum pmcmsptwi_xfer_result pmcmsptwi_xfer_cmd(
+ struct pmcmsptwi_cmd *cmd,
+ struct pmcmsptwi_data *data)
+{
+ enum pmcmsptwi_xfer_result retval;
+
+ if ((cmd->type == MSP_TWI_CMD_WRITE && cmd->write_len == 0) ||
+ (cmd->type == MSP_TWI_CMD_READ && cmd->read_len == 0) ||
+ (cmd->type == MSP_TWI_CMD_WRITE_READ &&
+ (cmd->read_len == 0 || cmd->write_len == 0))) {
+ dev_err(&pmcmsptwi_adapter.dev,
+ "%s: Cannot transfer less than 1 byte\n",
+ __FUNCTION__);
+ return -EINVAL;
+ }
+
+ if (cmd->read_len > MSP_MAX_BYTES_PER_RW ||
+ cmd->write_len > MSP_MAX_BYTES_PER_RW) {
+ dev_err(&pmcmsptwi_adapter.dev,
+ "%s: Cannot transfer more than %d bytes\n",
+ __FUNCTION__, MSP_MAX_BYTES_PER_RW);
+ return -EINVAL;
+ }
+
+ mutex_lock(&data->lock);
+ dev_dbg(&pmcmsptwi_adapter.dev,
+ "Setting address to 0x%04x\n", cmd->addr);
+ pmcmsptwi_writel(cmd->addr, data->iobase + MSP_TWI_ADD_REG_OFFSET);
+
+ if (cmd->type == MSP_TWI_CMD_WRITE ||
+ cmd->type == MSP_TWI_CMD_WRITE_READ) {
+ __be64 tmp = cpu_to_be64p((u64 *)cmd->write_data);
+ tmp >>= (MSP_MAX_BYTES_PER_RW - cmd->write_len) * 8;
+ dev_dbg(&pmcmsptwi_adapter.dev, "Writing 0x%016llx\n", tmp);
+ pmcmsptwi_writel(tmp & 0x00000000ffffffffLL,
+ data->iobase + MSP_TWI_DAT_0_REG_OFFSET);
+ if (cmd->write_len > 4)
+ pmcmsptwi_writel(tmp >> 32,
+ data->iobase + MSP_TWI_DAT_1_REG_OFFSET);
+ }
+
+ retval = pmcmsptwi_do_xfer(pmcmsptwi_cmd_to_reg(cmd), data);
+ if (retval != MSP_TWI_XFER_OK)
+ goto xfer_err;
+
+ if (cmd->type == MSP_TWI_CMD_READ ||
+ cmd->type == MSP_TWI_CMD_WRITE_READ) {
+ int i;
+ u64 rmsk = ~(0xffffffffffffffffLL << (cmd->read_len * 8));
+ u64 tmp = (u64)pmcmsptwi_readl(data->iobase +
+ MSP_TWI_DAT_0_REG_OFFSET);
+ if (cmd->read_len > 4)
+ tmp |= (u64)pmcmsptwi_readl(data->iobase +
+ MSP_TWI_DAT_1_REG_OFFSET) << 32;
+ tmp &= rmsk;
+ dev_dbg(&pmcmsptwi_adapter.dev, "Read 0x%016llx\n", tmp);
+
+ for (i = 0; i < cmd->read_len; i++)
+ cmd->read_data[i] = tmp >> i;
+ }
+
+xfer_err:
+ mutex_unlock(&data->lock);
+
+ return retval;
+}
+
+/* -- Algorithm functions -- */
+
+/*
+ * Sends an i2c command out on the adapter
+ */
+static int pmcmsptwi_master_xfer(struct i2c_adapter *adap,
+ struct i2c_msg *msg, int num)
+{
+ struct pmcmsptwi_data *data = i2c_get_adapdata(adap);
+ struct pmcmsptwi_cmd cmd;
+ struct pmcmsptwi_cfg oldcfg, newcfg;
+ int ret;
+
+ if (num > 2) {
+ dev_dbg(&adap->dev, "%d messages unsupported\n", num);
+ return -EINVAL;
+ } else if (num == 2) {
+ /* Check for a dual write-then-read command */
+ struct i2c_msg *nextmsg = msg + 1;
+ if (!(msg->flags & I2C_M_RD) &&
+ (nextmsg->flags & I2C_M_RD) &&
+ msg->addr == nextmsg->addr) {
+ cmd.type = MSP_TWI_CMD_WRITE_READ;
+ cmd.write_len = msg->len;
+ cmd.write_data = msg->buf;
+ cmd.read_len = nextmsg->len;
+ cmd.read_data = nextmsg->buf;
+ } else {
+ dev_dbg(&adap->dev,
+ "Non write-read dual messages unsupported\n");
+ return -EINVAL;
+ }
+ } else if (msg->flags & I2C_M_RD) {
+ cmd.type = MSP_TWI_CMD_READ;
+ cmd.read_len = msg->len;
+ cmd.read_data = msg->buf;
+ cmd.write_len = 0;
+ cmd.write_data = NULL;
+ } else {
+ cmd.type = MSP_TWI_CMD_WRITE;
+ cmd.read_len = 0;
+ cmd.read_data = NULL;
+ cmd.write_len = msg->len;
+ cmd.write_data = msg->buf;
+ }
+
+ if (msg->len == 0) {
+ dev_err(&adap->dev, "Zero-byte messages unsupported\n");
+ return -EINVAL;
+ }
+
+ cmd.addr = msg->addr;
+
+ if (msg->flags & I2C_M_TEN) {
+ pmcmsptwi_get_twi_config(&newcfg, data);
+ memcpy(&oldcfg, &newcfg, sizeof(oldcfg));
+
+ /* Set the special 10-bit address flag */
+ newcfg.add10 = 1;
+
+ pmcmsptwi_set_twi_config(&newcfg, data);
+ }
+
+ /* Execute the command */
+ ret = pmcmsptwi_xfer_cmd(&cmd, data);
+
+ if (msg->flags & I2C_M_TEN)
+ pmcmsptwi_set_twi_config(&oldcfg, data);
+
+ dev_dbg(&adap->dev, "I2C %s of %d bytes ",
+ (msg->flags & I2C_M_RD) ? "read" : "write", msg->len);
+ if (ret != MSP_TWI_XFER_OK) {
+ /*
+ * TODO: We could potentially loop and retry in the case
+ * of MSP_TWI_XFER_TIMEOUT.
+ */
+ dev_dbg(&adap->dev, "failed\n");
+ return -1;
+ }
+
+ dev_dbg(&adap->dev, "succeeded\n");
+ return 0;
+}
+
+static u32 pmcmsptwi_i2c_func(struct i2c_adapter *adapter)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR |
+ I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_PROC_CALL;
+}
+
+/* -- Initialization -- */
+
+static struct i2c_algorithm pmcmsptwi_algo = {
+ .master_xfer = pmcmsptwi_master_xfer,
+ .functionality = pmcmsptwi_i2c_func,
+};
+
+static struct i2c_adapter pmcmsptwi_adapter = {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON,
+ .algo = &pmcmsptwi_algo,
+ .name = DRV_NAME,
+};
+
+static struct platform_driver pmcmsptwi_driver = {
+ .probe = pmcmsptwi_probe,
+ .remove = __devexit_p(pmcmsptwi_remove),
+ .driver {
+ .name = DRV_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init pmcmsptwi_init(void)
+{
+ return platform_driver_register(&pmcmsptwi_driver);
+}
+
+static void __exit pmcmsptwi_exit(void)
+{
+ platform_driver_unregister(&pmcmsptwi_driver);
+}
+
+MODULE_DESCRIPTION("PMC MSP TWI/SMBus/I2C driver");
+MODULE_LICENSE("GPL");
+
+module_init(pmcmsptwi_init);
+module_exit(pmcmsptwi_exit);