Implements the basic driver for TPS6235x devices populated on the
PR785 board. tps6235x.c contains the driver code for TPS devices used on
PR785 boards. Driver code is added it to the build.
Signed-off-by: Manikandan Pillai <mani.pillai@xxxxxx>
---
drivers/i2c/chips/Makefile | 1 +
drivers/i2c/chips/tps6235x.c | 416 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 417 insertions(+), 0 deletions(-)
create mode 100644 drivers/i2c/chips/tps6235x.c
diff --git a/drivers/i2c/chips/Makefile b/drivers/i2c/chips/Makefile
index cb9f2bb..749f1ec 100644
--- a/drivers/i2c/chips/Makefile
+++ b/drivers/i2c/chips/Makefile
@@ -31,6 +31,7 @@ obj-$(CONFIG_TWL4030_PWRBUTTON) += twl4030-pwrbutton.o
obj-$(CONFIG_TWL4030_MADC) += twl4030-madc.o
obj-$(CONFIG_RTC_X1205_I2C) += x1205.o
obj-$(CONFIG_LP5521) += lp5521.o
+obj-$(CONFIG_TPS6235X) += tps6235x.o
ifeq ($(CONFIG_I2C_DEBUG_CHIP),y)
EXTRA_CFLAGS += -DDEBUG
diff --git a/drivers/i2c/chips/tps6235x.c b/drivers/i2c/chips/tps6235x.c
new file mode 100644
index 0000000..fd5ee0b
--- /dev/null
+++ b/drivers/i2c/chips/tps6235x.c
@@ -0,0 +1,416 @@
+/*
+ * drivers/i2c/chips/tps6235x.c
+ *
+ * TI TPS6235x device driver
+ *
+ * Copyright (C) 2008 Texas Instruments Inc
+ *
+ * Contributors:
+ * Manikandan Pillai <mani.pillai@xxxxxx>
+ *
+ * This package is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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/i2c.h>
+#include <linux/delay.h>
+
+#define MODULE_NAME "tps6235x_power"
+
+/* Debug functions */
+#ifdef DEBUG
+
+#define dump_reg(client, reg, val) \
+ do { \
+ tps6235x_read_reg(client, reg, &val); \
+ dev_dbg(&(client)->dev, "Reg(0x%.2X): 0x%.2X\n", reg, val); \
+ } while (0)
+
+#endif /* #ifdef DEBUG */
+
+/* 2 I2C devices on PR785 board for controlling voltage on CORE and MPU */
+typedef enum TPS_module_type {
+ PR785_CORE_PWR,
+ PR785_MPU_PWR,
+} TPS_module_type;
+
+#define TPS6235X_REG_VSEL0 0
+#define TPS6235X_REG_VSEL1 1
+#define TPS6235X_REG_CTRL1 2
+#define TPS6235X_REG_CTRL2 3
+#define TPS6235X_REG_MAX TPS6235X_REG_CTRL2
+
+/* Device addresses for PR785 card */
+#define PR785_62352_CORE_ADDR 0x4A
+#define PR785_62353_MPU_ADDR 0x48
+
+/* Minimum and Maximum dc-dc voltage supported by the TPS6235x devices
+All voltages given in millivolts */
+#define PR785_MIN_CORE_VOLT 750
+#define PR785_MAX_CORE_VOLT 1537
+#define PR785_MIN_MPU_VOLT 750
+#define PR785_MAX_MPU_VOLT 1537
+
+/* Maximum number of bytes to be read in a single read */
+#define PR785_RETRY_COUNT 0x3
+
+/* Register bit settings */
+#define TPS6235X_EN_DCDC (0x1 << 0x7)
+#define TPS6235X_VSM_MSK (0x3F)
+#define TPS6235X_EN_SYN_MSK (0x1 << 0x5)
+#define TPS6235X_SW_VOLT_MSK (0x1 << 0x4)
+#define TPS6235X_PWR_OK_MSK (0x1 << 0x5)
+#define TPS6235X_OUT_DIS_MSK (0x1 << 0x6)
+#define TPS6235X_GO_MSK (0x1 << 0x7)
+
+struct tps_6235x_info {
+ unsigned int state;
+ enum TPS_module_type tps_i2c_addr;
+ struct i2c_client *client;
+ struct device *i2c_dev;
+ /* platform data holder */
+ void *pdata;
+};
+
+static struct tps_6235x_info tps_6235x_infodata[2];
+
+/*
+ * Get client pointer for a particular device
+ * Returns zero if successful, or non-zero otherwise.
+ */
+static struct i2c_client *tps_6235x_get_client(TPS_module_type tps_mod_type)
+{
+ if (tps_mod_type == PR785_CORE_PWR)
+ return tps_6235x_infodata[0].client;
+ else if (tps_mod_type == PR785_MPU_PWR)
+ return tps_6235x_infodata[1].client;
+ else
+ return NULL;
+}
+
+/*
+ * Read a value from a register in an tps_6235x device.
+ * The value is returned in 'val'.
+ * Returns zero if successful, or non-zero otherwise.
+ */
+static int tps_6235x_read_reg(struct i2c_client *client, u8 reg, u8 *val)
+{
+ int err;
+ struct i2c_msg msg[2];
+ u8 data;
+
+ if (!client->adapter)
+ return -ENODEV;
+
+ /* [MSG1] fill the register address data */
+ data = reg;
+ msg[0].addr = client->addr;
+ msg[0].len = 1;
+ msg[0].flags = 0;
+ msg[0].buf = &data;
+
+ /* [MSG2] fill the data rx buffer */
+ msg[1].addr = client->addr;
+ msg[1].len = 1; /* only 1 byte */
+ msg[1].flags = I2C_M_RD; /* Read the register values */
+ msg[1].buf = val;
+ err = i2c_transfer(client->adapter, msg, 2);
+ if (err >= 0)
+ return 0;
+
+ dev_err(&client->dev,
+ "read from device 0x%.2x, offset 0x%.2x error %d\n",
+ client->addr, reg, err);
+
+ return err;
+}
+
+/*
+ * Write a value to a register in an tps_6235x device.
+ * Returns zero if successful, or non-zero otherwise.
+ */
+static int tps_6235x_write_reg(struct i2c_client *client, u8 reg, u8 val)
+{
+ int err;
+ int retry = 0;
+ struct i2c_msg msg[1];
+ u8 data[2];
+
+ if (!client->adapter)
+ return -ENODEV;
+
+again:
+ data[0] = reg; /* Register offset */
+ data[1] = val; /* Register value */
+ msg->addr = client->addr;
+ msg->len = 2;
+ msg->flags = 0; /* write operation */
+ msg->buf = data;
+
+ err = i2c_transfer(client->adapter, msg, 1);
+ if (err >= 0)
+ return 0;
+
+ dev_err(&client->dev,
+ "wrote 0x%.2x to offset 0x%.2x error %d\n", val, reg, err);
+
+ if (retry <= PR785_RETRY_COUNT) {
+ dev_info(&client->dev, "retry ... %d\n", retry);
+ retry++;
+ schedule_timeout(msecs_to_jiffies(20));
+ goto again;
+ }
+ return err;
+}
+
+/**
+* pwr_i2c_read - Allows the caller to read one register from TPS device
+* based on the address given. For the PR785 it reads
+* only 1 byte into a specified register
+* tps_mod_type - Enum for the device to be read
+* reg - Register to be read from(value has to be between 0-3
+* val - value read from the reg
+* Retval - 0 -> Success else non-zero
+**/
+int pwr_i2c_read(TPS_module_type tps_mod_type, u8 reg, u8 *val)
+{
+ struct i2c_client *client;
+
+ client = tps_6235x_get_client(tps_mod_type);
+ /* check if register is less than <= 3 Register is 0 -3 */
+ if (reg > TPS6235X_REG_MAX)
+ return -1;
+
+ return tps_6235x_read_reg(client, reg, val);
+}
+EXPORT_SYMBOL(pwr_i2c_read);
+
+/**
+* pwr_i2c_write - Allows the caller to write one register from TPS device
+* based on the address given. For the PR785 it writes
+* only 1 byte into a specified register
+* tps_mod_type - Enum for the device to be written
+* reg - Register to be written to(value has to be between 0-3
+* val - value to be written to reg
+* Retval - 0 -> Success else non-zero
+**/
+int pwr_i2c_write(TPS_module_type tps_mod_type, u8 reg, u8 val)
+{
+ struct i2c_client *client;
+
+ client = tps_6235x_get_client(tps_mod_type);
+
+ /* check if register is less than <= 3 Register is 0 -3 */
+ if (reg > TPS6235X_REG_MAX)
+ return -1;
+
+ return tps_6235x_write_reg(client, reg, val);
+}
+EXPORT_SYMBOL(pwr_i2c_write);
+
+/**
+* TPSPR785 - Specific functions
+* pr785_enbl_dcdc - Allows the caller to enable or disable the TPS6235x device
+* on the PR785 board. The voltage for PR785 is selected by
+* VSEL1 register since VSEL pin is kept high
+*
+* flag - 1 == enable 0 == disable
+* Retval - 0 -> Success else non-zero
+**/
+int pr785_enbl_dcdc(TPS_module_type tps_mod_type, unsigned int en_flag)
+{
+ unsigned char vsel1;
+ int ret;
+
+ ret = pwr_i2c_read(tps_mod_type, TPS6235X_REG_VSEL1, &vsel1);
+ if (ret == 0) {
+ if (en_flag)
+ vsel1 |= TPS6235X_EN_DCDC;
+ else
+ vsel1 &= ~(TPS6235X_EN_DCDC);
+ ret = pwr_i2c_write(tps_mod_type, TPS6235X_REG_VSEL1, vsel1);
+ }
+ return ret;
+}
+EXPORT_SYMBOL(pr785_enbl_dcdc);
+
+
+/**
+* TPSPR785 - Specific functions
+* pr785_set_dcdc_volt - Allows the caller to set a particular voltage on
+* for CORE or MPU
+*
+* voltage - voltage to be set in millivolts (75--1537)
+* Retval - 0 -> Success else non-zero
+**/
+int pr785_set_dcdc_volt(TPS_module_type tps_mod_type, unsigned int millivolts)
+{
+ unsigned char vsel1;
+ unsigned int volt;
+
+ /* check if the millivolts is within range */
+ if ((millivolts < PR785_MIN_CORE_VOLT) ||
+ (millivolts > PR785_MAX_CORE_VOLT))
+ return -1;
+
+ /* Output voltage set is = min_op_volt + ( VSM * 12.5mv) */
+ volt = millivolts - PR785_MIN_CORE_VOLT;
+ volt /= 25;
+ volt *= 2;
+ vsel1 = ((TPS6235X_EN_DCDC) | (volt & TPS6235X_VSM_MSK));
+ return pwr_i2c_write(tps_mod_type, TPS6235X_REG_VSEL1, vsel1);
+}
+EXPORT_SYMBOL(pr785_set_dcdc_volt);
+
+/**
+* TPSPR785 - Specific functions
+* pr785_get_dcdc_volt - Allows the caller to get the set voltage on a
+* particular TPS 6235x device on PR785 card
+*
+* voltage - voltage to be set in millivolts (75--1537)
+* Retval - 0 -> Success else non-zero
+**/
+int pr785_get_dcdc_volt(TPS_module_type tps_mod_type, unsigned int *millivolts)
+{
+ unsigned char vsel1;
+ unsigned int volt;
+
+ /* Read the VSEL1 register to get VSM */
+ pwr_i2c_read(tps_mod_type, TPS6235X_REG_VSEL1, &vsel1);
+ /* Output voltage set is = min_op_volt + ( VSM * 12.5mv) */
+ /* To cut out floating point operation we will multiply by 25
+ divide by 2 */
+ volt = (((vsel1 & TPS6235X_VSM_MSK) * 25) / 2) + PR785_MIN_CORE_VOLT;
+ *millivolts = volt;
+ return 0;
+}
+EXPORT_SYMBOL(pr785_get_dcdc_volt);
+
+/**
+ * tps_6235x_probe - TPS6235x driver i2c probe handler
+ * @client: i2c driver client device structure
+ *
+ * Register PR785 as an i2c client device driver
+ */
+static struct i2c_driver tps_6235x_i2c_driver;
+
+static
+int tps_6235x_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ unsigned char reg_val;
+
+ printk(KERN_INFO "tps_6235x_probe:TPS addr = %x\n", (int)client->addr);
+
+ if (i2c_get_clientdata(client))
+ return -EBUSY;
+
+ /* Device probed is TPS62352 CORE pwr chip if driver_data = 0 */
+ /* Device probed is TPS62353 MPU pwr chip if driver_data = 1 */
+ tps_6235x_infodata[id->driver_data].client = client;
+ tps_6235x_infodata[id->driver_data].tps_i2c_addr = client->addr;
+ tps_6235x_infodata[id->driver_data].state = 1;
+ tps_6235x_infodata[id->driver_data].i2c_dev = &client->dev;
+
+ tps_6235x_read_reg(client, TPS6235X_REG_CTRL2, ®_val);
+ reg_val |= (TPS6235X_OUT_DIS_MSK | TPS6235X_GO_MSK);
+ tps_6235x_write_reg(client, TPS6235X_REG_CTRL2, reg_val);
+ tps_6235x_read_reg(client, TPS6235X_REG_CTRL2, ®_val);
+
+ if (reg_val & TPS6235X_PWR_OK_MSK)
+ printk(KERN_INFO "Power is OK %x\n", reg_val);
+ else
+ printk(KERN_INFO "Power not within range = %x\n", reg_val);
+ return 0;
+}
+
+/**
+ * tps_6235x_remove - TPS6235x driver i2c remove handler
+ * @client: i2c driver client device structure
+ *
+ * UnregisterPR785 as an i2c client device driver
+ */
+static int __exit tps_6235x_remove(struct i2c_client *client)
+{
+#ifdef DEBUG
+ printk(KERN_INFO "tps_6235x_remove invoked\n");
+#endif
+
+ if (!client->adapter)
+ return -ENODEV; /* our client isn't attached */
+
+ i2c_set_clientdata(client, NULL);
+
+ return 0;
+}
+
+static const struct i2c_device_id tps_6235x_id[] = {
+ { "tps62352_core_pwr", 0},
+ { "tps62353_mpu_pwr", 1},
+ {},
+};
+
+MODULE_DEVICE_TABLE(i2c, tps_6235x_id);
+
+static struct i2c_driver tps_6235x_i2c_driver = {
+ .driver = {
+ .name = "tps6235x_power",
+ .owner = THIS_MODULE,
+ },
+ .probe = tps_6235x_probe,
+ .remove = __exit_p(tps_6235x_remove),
+ .id_table = tps_6235x_id,
+};
+
+/**
+ * tps_6235x_init
+ *
+ * Module init function
+ */
+static int __init tps_6235x_init(void)
+{
+ int err;
+
+#ifdef DEBUG
+ printk(KERN_INFO "tps_6235x_init invoked\n");
+#endif
+
+ err = i2c_add_driver(&tps_6235x_i2c_driver);
+ if (err) {
+ printk(KERN_ERR "Failed to register " MODULE_NAME ".\n");
+ return err;
+ } else {
+ printk(KERN_INFO "I2c driver registered\n");
+ }
+ return 0;
+}
+
+/**
+ * tps_6235x_cleanup
+ *
+ * Module exit function
+ */
+static void __exit tps_6235x_cleanup(void)
+{
+#ifdef DEBUG
+ printk(KERN_INFO "tps_6235x_cleanup invoked\n");
+#endif
+ i2c_del_driver(&tps_6235x_i2c_driver);
+}
+
+late_initcall(tps_6235x_init);
+module_exit(tps_6235x_cleanup);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("TPS6235x based PR785 linux driver");
+MODULE_LICENSE("GPL");
--
1.5.6
--
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