Re: [PATCH 02/12] hwmon: lis3: regulator control

From: Jonathan Cameron
Date: Fri Oct 22 2010 - 12:06:13 EST

On 10/22/10 12:57, Samu Onkalo wrote:
> Based on pm_runtime control, turn lis3 regulators on and off.
> Perform context save and restore on transitions.
>
> Feature is optional and must be enabled in platform data.
Answers all my queries on the previous version
>
> Signed-off-by: Samu Onkalo <samu.p.onkalo@xxxxxxxxx>
Acked-by: Jonathan Cameron <jic23@xxxxxxxxx>
> ---
> drivers/hwmon/lis3lv02d.c | 52 ++++++++++++++++++++++++++++++++++++++
> drivers/hwmon/lis3lv02d.h | 12 +++++++++
> drivers/hwmon/lis3lv02d_i2c.c | 55 ++++++++++++++++++++++++++++++++++++++++-
> include/linux/lis3lv02d.h | 2 +
> 4 files changed, 120 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/hwmon/lis3lv02d.c b/drivers/hwmon/lis3lv02d.c
> index 412ddc3..ade6f3a 100644
> --- a/drivers/hwmon/lis3lv02d.c
> +++ b/drivers/hwmon/lis3lv02d.c
> @@ -31,6 +31,7 @@
> #include <linux/delay.h>
> #include <linux/wait.h>
> #include <linux/poll.h>
> +#include <linux/slab.h>
> #include <linux/freezer.h>
> #include <linux/uaccess.h>
> #include <linux/miscdevice.h>
> @@ -223,10 +224,46 @@ fail:
> return ret;
> }
>
> +/*
> + * Order of registers in the list affects to order of the restore process.
> + * Perhaps it is a good idea to set interrupt enable register as a last one
> + * after all other configurations
> + */
> +static u8 lis3_wai8_regs[] = { FF_WU_CFG_1, FF_WU_THS_1, FF_WU_DURATION_1,
> + FF_WU_CFG_2, FF_WU_THS_2, FF_WU_DURATION_2,
> + CLICK_CFG, CLICK_SRC, CLICK_THSY_X, CLICK_THSZ,
> + CLICK_TIMELIMIT, CLICK_LATENCY, CLICK_WINDOW,
> + CTRL_REG1, CTRL_REG2, CTRL_REG3};
> +
> +static u8 lis3_wai12_regs[] = {FF_WU_CFG, FF_WU_THS_L, FF_WU_THS_H,
> + FF_WU_DURATION, DD_CFG, DD_THSI_L, DD_THSI_H,
> + DD_THSE_L, DD_THSE_H,
> + CTRL_REG1, CTRL_REG3, CTRL_REG2};
> +
> +static inline void lis3_context_save(struct lis3lv02d *lis3)
> +{
> + int i;
> + for (i = 0; i < lis3->regs_size; i++)
> + lis3->read(lis3, lis3->regs[i], &lis3->reg_cache[i]);
> + lis3->regs_stored = true;
> +}
> +
> +static inline void lis3_context_restore(struct lis3lv02d *lis3)
> +{
> + int i;
> + if (lis3->regs_stored)
> + for (i = 0; i < lis3->regs_size; i++)
> + lis3->write(lis3, lis3->regs[i], lis3->reg_cache[i]);
> +}
> +
> void lis3lv02d_poweroff(struct lis3lv02d *lis3)
> {
> + if (lis3->reg_ctrl)
> + lis3_context_save(lis3);
> /* disable X,Y,Z axis and power down */
> lis3->write(lis3, CTRL_REG1, 0x00);
> + if (lis3->reg_ctrl)
> + lis3->reg_ctrl(lis3, LIS3_REG_OFF);
> }
> EXPORT_SYMBOL_GPL(lis3lv02d_poweroff);
>
> @@ -249,6 +286,8 @@ void lis3lv02d_poweron(struct lis3lv02d *lis3)
> reg |= CTRL2_BDU;
> lis3->write(lis3, CTRL_REG2, reg);
> }
> + if (lis3->reg_ctrl)
> + lis3_context_restore(lis3);
> }
> EXPORT_SYMBOL_GPL(lis3lv02d_poweron);
>
> @@ -640,6 +679,7 @@ int lis3lv02d_remove_fs(struct lis3lv02d *lis3)
> pm_runtime_disable(lis3->pm_dev);
> pm_runtime_set_suspended(lis3->pm_dev);
> }
> + kfree(lis3->reg_cache);
> return 0;
> }
> EXPORT_SYMBOL_GPL(lis3lv02d_remove_fs);
> @@ -719,6 +759,8 @@ int lis3lv02d_init_device(struct lis3lv02d *dev)
> dev->odrs = lis3_12_rates;
> dev->odr_mask = CTRL1_DF0 | CTRL1_DF1;
> dev->scale = LIS3_SENSITIVITY_12B;
> + dev->regs = lis3_wai12_regs;
> + dev->regs_size = ARRAY_SIZE(lis3_wai12_regs);
> break;
> case WAI_8B:
> printk(KERN_INFO DRIVER_NAME ": 8 bits sensor found\n");
> @@ -728,6 +770,8 @@ int lis3lv02d_init_device(struct lis3lv02d *dev)
> dev->odrs = lis3_8_rates;
> dev->odr_mask = CTRL1_DR;
> dev->scale = LIS3_SENSITIVITY_8B;
> + dev->regs = lis3_wai8_regs;
> + dev->regs_size = ARRAY_SIZE(lis3_wai8_regs);
> break;
> default:
> printk(KERN_ERR DRIVER_NAME
> @@ -735,6 +779,14 @@ int lis3lv02d_init_device(struct lis3lv02d *dev)
> return -EINVAL;
> }
>
> + dev->reg_cache = kzalloc(max(sizeof(lis3_wai8_regs),
> + sizeof(lis3_wai12_regs)), GFP_KERNEL);
> +
> + if (dev->reg_cache == NULL) {
> + printk(KERN_ERR DRIVER_NAME "out of memory\n");
> + return -ENOMEM;
> + }
> +
> mutex_init(&dev->mutex);
>
> lis3lv02d_add_fs(dev);
> diff --git a/drivers/hwmon/lis3lv02d.h b/drivers/hwmon/lis3lv02d.h
> index 3e8a208..7661e59 100644
> --- a/drivers/hwmon/lis3lv02d.h
> +++ b/drivers/hwmon/lis3lv02d.h
> @@ -20,6 +20,7 @@
> */
> #include <linux/platform_device.h>
> #include <linux/input-polldev.h>
> +#include <linux/regulator/consumer.h>
>
> /*
> * This driver tries to support the "digital" accelerometer chips from
> @@ -206,6 +207,11 @@ enum lis3lv02d_click_src_8b {
> CLICK_IA = 0x40,
> };
>
> +enum lis3lv02d_reg_state {
> + LIS3_REG_OFF = 0x00,
> + LIS3_REG_ON = 0x01,
> +};
> +
> struct axis_conversion {
> s8 x;
> s8 y;
> @@ -218,8 +224,13 @@ struct lis3lv02d {
> int (*init) (struct lis3lv02d *lis3);
> int (*write) (struct lis3lv02d *lis3, int reg, u8 val);
> int (*read) (struct lis3lv02d *lis3, int reg, u8 *ret);
> + int (*reg_ctrl) (struct lis3lv02d *lis3, bool state);
>
> int *odrs; /* Supported output data rates */
> + u8 *regs; /* Regs to store / restore */
> + int regs_size;
> + u8 *reg_cache;
> + bool regs_stored;
> u8 odr_mask; /* ODR bit mask */
> u8 whoami; /* indicates measurement precision */
> s16 (*read_data) (struct lis3lv02d *lis3, int reg);
> @@ -232,6 +243,7 @@ struct lis3lv02d {
>
> struct input_polled_dev *idev; /* input device */
> struct platform_device *pdev; /* platform device */
> + struct regulator_bulk_data regulators[2];
> atomic_t count; /* interrupt count after last read */
> struct axis_conversion ac; /* hw -> logical axis */
> int mapped_btns[3];
> diff --git a/drivers/hwmon/lis3lv02d_i2c.c b/drivers/hwmon/lis3lv02d_i2c.c
> index 6e965d7..98983cc 100644
> --- a/drivers/hwmon/lis3lv02d_i2c.c
> +++ b/drivers/hwmon/lis3lv02d_i2c.c
> @@ -30,10 +30,29 @@
> #include <linux/err.h>
> #include <linux/i2c.h>
> #include <linux/pm_runtime.h>
> +#include <linux/delay.h>
> #include "lis3lv02d.h"
>
> #define DRV_NAME "lis3lv02d_i2c"
>
> +static const char reg_vdd[] = "Vdd";
> +static const char reg_vdd_io[] = "Vdd_IO";
> +
> +static int lis3_reg_ctrl(struct lis3lv02d *lis3, bool state)
> +{
> + int ret;
> + if (state == LIS3_REG_OFF) {
> + ret = regulator_bulk_disable(ARRAY_SIZE(lis3->regulators),
> + lis3->regulators);
> + } else {
> + ret = regulator_bulk_enable(ARRAY_SIZE(lis3->regulators),
> + lis3->regulators);
> + /* Chip needs time to wakeup. Not mentioned in datasheet */
> + usleep_range(10000, 20000);
> + }
> + return ret;
> +}
> +
> static inline s32 lis3_i2c_write(struct lis3lv02d *lis3, int reg, u8 value)
> {
> struct i2c_client *c = lis3->bus_priv;
> @@ -52,6 +71,13 @@ static int lis3_i2c_init(struct lis3lv02d *lis3)
> u8 reg;
> int ret;
>
> + if (lis3->reg_ctrl)
> + lis3_reg_ctrl(lis3, LIS3_REG_ON);
> +
> + lis3->read(lis3, WHO_AM_I, &reg);
> + if (reg != lis3->whoami)
> + printk(KERN_ERR "lis3: power on failure\n");
> +
> /* power up the device */
> ret = lis3->read(lis3, CTRL_REG1, &reg);
> if (ret < 0)
> @@ -73,6 +99,10 @@ static int __devinit lis3lv02d_i2c_probe(struct i2c_client *client,
> struct lis3lv02d_platform_data *pdata = client->dev.platform_data;
>
> if (pdata) {
> + /* Regulator control is optional */
> + if (pdata->driver_features & LIS3_USE_REGULATOR_CTRL)
> + lis3_dev.reg_ctrl = lis3_reg_ctrl;
> +
> if (pdata->axis_x)
> lis3lv02d_axis_map.x = pdata->axis_x;
>
> @@ -89,6 +119,16 @@ static int __devinit lis3lv02d_i2c_probe(struct i2c_client *client,
> goto fail;
> }
>
> + if (lis3_dev.reg_ctrl) {
> + lis3_dev.regulators[0].supply = reg_vdd;
> + lis3_dev.regulators[1].supply = reg_vdd_io;
> + ret = regulator_bulk_get(&client->dev,
> + ARRAY_SIZE(lis3_dev.regulators),
> + lis3_dev.regulators);
> + if (ret < 0)
> + goto fail;
> + }
> +
> lis3_dev.pdata = pdata;
> lis3_dev.bus_priv = client;
> lis3_dev.init = lis3_i2c_init;
> @@ -99,21 +139,34 @@ static int __devinit lis3lv02d_i2c_probe(struct i2c_client *client,
> lis3_dev.pm_dev = &client->dev;
>
> i2c_set_clientdata(client, &lis3_dev);
> +
> + /* Provide power over the init call */
> + if (lis3_dev.reg_ctrl)
> + lis3_reg_ctrl(&lis3_dev, LIS3_REG_ON);
> +
> ret = lis3lv02d_init_device(&lis3_dev);
> +
> + if (lis3_dev.reg_ctrl)
> + lis3_reg_ctrl(&lis3_dev, LIS3_REG_OFF);
> fail:
> return ret;
> }
>
> static int __devexit lis3lv02d_i2c_remove(struct i2c_client *client)
> {
> + struct lis3lv02d *lis3 = i2c_get_clientdata(client);
> struct lis3lv02d_platform_data *pdata = client->dev.platform_data;
>
> if (pdata && pdata->release_resources)
> pdata->release_resources();
>
> lis3lv02d_joystick_disable();
> + lis3lv02d_remove_fs(&lis3_dev);
>
> - return lis3lv02d_remove_fs(&lis3_dev);
> + if (lis3_dev.reg_ctrl)
> + regulator_bulk_free(ARRAY_SIZE(lis3->regulators),
> + lis3_dev.regulators);
> + return 0;
> }
>
> #ifdef CONFIG_PM
> diff --git a/include/linux/lis3lv02d.h b/include/linux/lis3lv02d.h
> index 0e8a346..c4a4a52 100644
> --- a/include/linux/lis3lv02d.h
> +++ b/include/linux/lis3lv02d.h
> @@ -64,6 +64,8 @@ struct lis3lv02d_platform_data {
> s8 axis_x;
> s8 axis_y;
> s8 axis_z;
> +#define LIS3_USE_REGULATOR_CTRL 0x01
> + u16 driver_features;
> int (*setup_resources)(void);
> int (*release_resources)(void);
> /* Limits for selftest are specified in chip data sheet */

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