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SubjectRe: [PATCH v2 05/10] LIS3LV02D: Proper power on sequence
Op 10-11-09 13:41, Samu Onkalo schreef:
> Lis3 accelerometer sensors have quite long power on delay (up to 125
> ms). This patch adds necessary delay to power on sequence for currently
> supported lis3 chips.
>
> Signed-off-by: Samu Onkalo <samu.p.onkalo@nokia.com>
Acked-by: Éric Piel <eric.piel@tremplin-utc.net>
> ---
> drivers/hwmon/lis3lv02d.c | 41 +++++++++++++++++++++++++++--------------
> drivers/hwmon/lis3lv02d.h | 1 +
> 2 files changed, 28 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/hwmon/lis3lv02d.c b/drivers/hwmon/lis3lv02d.c
> index b12ee35..39b9ac8 100644
> --- a/drivers/hwmon/lis3lv02d.c
> +++ b/drivers/hwmon/lis3lv02d.c
> @@ -50,6 +50,9 @@
> * joystick.
> */
>
> +#define LIS3_PWRON_DELAY_WAI_12B (5000)
> +#define LIS3_PWRON_DELAY_WAI_8B (3000)
> +
> struct lis3lv02d lis3_dev = {
> .misc_wait = __WAIT_QUEUE_HEAD_INITIALIZER(lis3_dev.misc_wait),
> };
> @@ -112,6 +115,24 @@ static void lis3lv02d_get_xyz(struct lis3lv02d *lis3, int *x, int *y, int *z)
> *z = lis3lv02d_get_axis(lis3->ac.z, position);
> }
>
> +/* conversion btw sampling rate and the register values */
> +static int lis3_12_rates[4] = {40, 160, 640, 2560};
> +static int lis3_8_rates[2] = {100, 400};
> +
> +static int lis3lv02d_get_odr(void)
> +{
> + u8 ctrl;
> + int val;
> +
> + lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
> +
> + if (lis3_dev.whoami == WAI_12B)
> + val = lis3_12_rates[(ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4];
> + else
> + val = lis3_8_rates[(ctrl & CTRL1_DR) >> 7];
> + return val;
> +}
> +
> void lis3lv02d_poweroff(struct lis3lv02d *lis3)
> {
> /* disable X,Y,Z axis and power down */
> @@ -125,6 +146,9 @@ void lis3lv02d_poweron(struct lis3lv02d *lis3)
>
> lis3->init(lis3);
>
> + /* LIS3 power on delay is quite long */
> + msleep(lis3->pwron_delay / lis3lv02d_get_odr());
> +
> /*
> * Common configuration
> * BDU: (12 bits sensors only) LSB and MSB values are not updated until
> @@ -364,23 +388,10 @@ static ssize_t lis3lv02d_calibrate_store(struct device *dev,
> return count;
> }
>
> -/* conversion btw sampling rate and the register values */
> -static int lis3_12_rates[4] = {40, 160, 640, 2560};
> -static int lis3_8_rates[2] = {100, 400};
> static ssize_t lis3lv02d_rate_show(struct device *dev,
> struct device_attribute *attr, char *buf)
> {
> - u8 ctrl;
> - int val;
> -
> - lis3_dev.read(&lis3_dev, CTRL_REG1, &ctrl);
> -
> - if (lis3_dev.whoami == WAI_12B)
> - val = lis3_12_rates[(ctrl & (CTRL1_DF0 | CTRL1_DF1)) >> 4];
> - else
> - val = lis3_8_rates[(ctrl & CTRL1_DR) >> 7];
> -
> - return sprintf(buf, "%d\n", val);
> + return sprintf(buf, "%d\n", lis3lv02d_get_odr());
> }
>
> static DEVICE_ATTR(position, S_IRUGO, lis3lv02d_position_show, NULL);
> @@ -430,11 +441,13 @@ int lis3lv02d_init_device(struct lis3lv02d *dev)
> printk(KERN_INFO DRIVER_NAME ": 12 bits sensor found\n");
> dev->read_data = lis3lv02d_read_12;
> dev->mdps_max_val = 2048;
> + dev->pwron_delay = LIS3_PWRON_DELAY_WAI_12B;
> break;
> case WAI_8B:
> printk(KERN_INFO DRIVER_NAME ": 8 bits sensor found\n");
> dev->read_data = lis3lv02d_read_8;
> dev->mdps_max_val = 128;
> + dev->pwron_delay = LIS3_PWRON_DELAY_WAI_8B;
> break;
> default:
> printk(KERN_ERR DRIVER_NAME
> diff --git a/drivers/hwmon/lis3lv02d.h b/drivers/hwmon/lis3lv02d.h
> index c6ae507..c57f21f 100644
> --- a/drivers/hwmon/lis3lv02d.h
> +++ b/drivers/hwmon/lis3lv02d.h
> @@ -202,6 +202,7 @@ struct lis3lv02d {
> u8 whoami; /* indicates measurement precision */
> s16 (*read_data) (struct lis3lv02d *lis3, int reg);
> int mdps_max_val;
> + int pwron_delay;
>
> struct input_polled_dev *idev; /* input device */
> struct platform_device *pdev; /* platform device */

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