On 10/01/10 12:46, Samu Onkalo wrote: > Based on pm_runtime control, turn lis3 regulators on and off. > Perform context save and restore on transitions. As this is a simple save and restore state patch I'm happy to comment on it. Mostly fine, though I have a couple of minor questions. > > Signed-off-by: Samu Onkalo <samu.p.onkalo@xxxxxxxxx> > --- > drivers/hwmon/lis3lv02d.c | 48 +++++++++++++++++++++++++++++++++++++++++ > drivers/hwmon/lis3lv02d.h | 19 ++++++++++++++++ > drivers/hwmon/lis3lv02d_i2c.c | 43 +++++++++++++++++++++++++++++++++++- > 3 files changed, 109 insertions(+), 1 deletions(-) > > diff --git a/drivers/hwmon/lis3lv02d.c b/drivers/hwmon/lis3lv02d.c > index eaa5bf0..23d47ad 100644 > --- a/drivers/hwmon/lis3lv02d.c > +++ b/drivers/hwmon/lis3lv02d.c > @@ -223,10 +223,46 @@ 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 +285,8 @@ 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); > > @@ -718,6 +756,8 @@ 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"); > @@ -727,6 +767,8 @@ 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 > @@ -734,6 +776,12 @@ int lis3lv02d_init_device(struct lis3lv02d *dev) > return -EINVAL; > } > This is a little odd as runtime checks go. Surely it can only occur in event of a clear driver bug? Personally I'd just go with dynamically allocating the reg_cache to be the right size... > + if (dev->regs_size > LIS3_NUM_MAX_REG) { > + printk(KERN_ERR DRIVER_NAME > + ": register cache area is too small"); > + return -EINVAL; > + } > + > mutex_init(&dev->mutex); > > lis3lv02d_add_fs(dev); > diff --git a/drivers/hwmon/lis3lv02d.h b/drivers/hwmon/lis3lv02d.h > index 3e8a208..caf3ed1 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 > @@ -97,6 +98,15 @@ enum lis3_who_am_i { > WAI_8B = 0x3B, /* 8 bits: LIS[23]02D[LQ]... */ > WAI_6B = 0x52, /* 6 bits: LIS331DLF - not supported */ > }; > +/* Number of RW registers in each device for register caching purposes */ You could just enforce this through review, but I guess it doesn't hurt to have sanity checks... > +#define NUM_RW_REGS_12B 21 > +#define NUM_RW_REGS_8B 15 > + > +#if NUM_RW_REGS_8B > NUM_RW_REGS_12B > +#define LIS3_NUM_MAX_REG NUM_RW_REGS_8B > +#else > +#define LIS3_NUM_MAX_REG NUM_RW_REGS_12B > +#endif > > enum lis3lv02d_ctrl1_12b { > CTRL1_Xen = 0x01, > @@ -206,6 +216,9 @@ enum lis3lv02d_click_src_8b { > CLICK_IA = 0x40, > }; > > +#define LIS3_REG_OFF 0x00 > +#define LIS3_REG_ON 0x01 I think the rest of these are done as enums. Worth doing that here for consistency? > + > struct axis_conversion { > s8 x; > s8 y; > @@ -218,8 +231,13 @@ 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; > + bool regs_stored; > + u8 reg_cache[LIS3_NUM_MAX_REG]; > u8 odr_mask; /* ODR bit mask */ > u8 whoami; /* indicates measurement precision */ > s16 (*read_data) (struct lis3lv02d *lis3, int reg); > @@ -232,6 +250,7 @@ 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 b9ed1fb..0852bed 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(5000, 10000); > + } > + return ret; > +} > + > static inline s32 lis3_i2c_write(struct lis3lv02d *lis3, int reg, u8 value) > { > struct i2c_client *c = lis3->bus_priv; > @@ -52,6 +71,12 @@ static int lis3_i2c_init(struct lis3lv02d *lis3) > u8 reg; > int ret; > > + lis3_reg_ctrl(lis3, LIS3_REG_ON); > + > + lis3->read(lis3, WHO_AM_I, ®); > + if (lis3->whoami != 0 && reg != lis3->whoami) What is the purpose of the first test? How can we get here without that being set? > + printk(KERN_ERR "lis3: power on failure\n"); > + > /* power up the device */ > ret = lis3->read(lis3, CTRL_REG1, ®); > if (ret < 0) > @@ -89,16 +114,29 @@ static int __devinit lis3lv02d_i2c_probe(struct i2c_client *client, > goto fail; > } > > + 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; > lis3_dev.read = lis3_i2c_read; > lis3_dev.write = lis3_i2c_write; > + lis3_dev.reg_ctrl = lis3_reg_ctrl; > lis3_dev.irq = client->irq; > lis3_dev.ac = lis3lv02d_axis_map; > lis3_dev.pm_dev = &client->dev; > > i2c_set_clientdata(client, &lis3_dev); > + > + /* Provide power over the init call */ > + lis3_reg_ctrl(&lis3_dev, LIS3_REG_ON); > + lis3_reg_ctrl(&lis3_dev, LIS3_REG_OFF); > + > ret = lis3lv02d_init_device(&lis3_dev); > fail: > return ret; > @@ -113,8 +151,11 @@ static int __devexit lis3lv02d_i2c_remove(struct i2c_client *client) > pdata->release_resources(); > > lis3lv02d_joystick_disable(); > + lis3lv02d_remove_fs(lis3); subtle change here... Out of intererst, why did the top level lis3_dev structure ever exist? (you can tell I haven't looked closely at this driver before!) Can remove_fs return an error? > > - return lis3lv02d_remove_fs(&lis3_dev); > + regulator_bulk_free(ARRAY_SIZE(lis3->regulators), > + lis3_dev.regulators); > + return 0; > } > > #ifdef CONFIG_PM -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html