| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 27 Jan 2016 10:21:26 +0900
From: Andi Shyti <andi.shyti@...sung.com>
To: Javier Martinez Canillas <javier@....samsung.com>
Cc: linux-kernel@...r.kernel.org, Kukjin Kim <kgene@...nel.org>,
rtc-linux@...glegroups.com, Chanwoo Choi <cw00.choi@...sung.com>,
Alexandre Belloni <alexandre.belloni@...e-electrons.com>,
Krzysztof Kozlowski <k.kozlowski@...sung.com>,
Laxman Dewangan <ldewangan@...dia.com>,
linux-samsung-soc@...r.kernel.org
Subject: Re: [PATCH v3 04/10] rtc: max77686: Use a driver data struct instead
hard-coded values
On Tue, Jan 26, 2016 at 04:20:14PM -0300, Javier Martinez Canillas wrote:
> The driver has some hard-coded values such as the minimum delay needed
> before a RTC update or the mask used for the sec/min/hour/etc registers.
>
> Use a data structure that contains these values and pass as driver data
> using the platform device ID table for each device.
>
> This allows to make the driver's ops callbacks more generic so other RTC
> that are similar but don't have the same values can also be supported.
>
> Signed-off-by: Javier Martinez Canillas <javier@....samsung.com>
> Acked-by: Laxman Dewangan <ldewangan@...dia.com>
Reviewed-by: Andi Shyti <andi.shyti@...sung.com>
> ---
>
> Changes in v3:
> - Fix max77686 delay. Suggested by Krzysztof Kozlowski.
> - Assign mask to u8 instead of int. Suggested by Krzysztof Kozlowski.
> - Add Laxman Dewangan's Acked-by tag to patch #4.
>
> Changes in v2:
> - Add a max77686 prefix to rtc_driver_data. Suggested by Krzysztof Kozlowski.
> - Comment about the .delay and .mask fields. Suggested by Krzysztof Kozlowski.
> - Change .mask type to u8. Suggested by Krzysztof Kozlowski.
> - Make .drv_data field const. Suggested by Krzysztof Kozlowski.
> - Don't cast to drop const on .drv_data asign. Suggested by Krzysztof Kozlowski.
> - Use platform_get_device_id() macro. Suggested by Krzysztof Kozlowski.
>
> drivers/rtc/rtc-max77686.c | 51 ++++++++++++++++++++++++++++++----------------
> 1 file changed, 34 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/rtc/rtc-max77686.c b/drivers/rtc/rtc-max77686.c
> index 025a17a95da3..8c4ca35029c3 100644
> --- a/drivers/rtc/rtc-max77686.c
> +++ b/drivers/rtc/rtc-max77686.c
> @@ -41,8 +41,6 @@
> #define ALARM_ENABLE_SHIFT 7
> #define ALARM_ENABLE_MASK (1 << ALARM_ENABLE_SHIFT)
>
> -#define MAX77686_RTC_UPDATE_DELAY 16000
> -
> enum {
> RTC_SEC = 0,
> RTC_MIN,
> @@ -54,6 +52,13 @@ enum {
> RTC_NR_TIME
> };
>
> +struct max77686_rtc_driver_data {
> + /* Minimum usecs needed for a RTC update */
> + unsigned long delay;
> + /* Mask used to read RTC registers value */
> + u8 mask;
> +};
> +
> struct max77686_rtc_info {
> struct device *dev;
> struct max77686_dev *max77686;
> @@ -63,6 +68,8 @@ struct max77686_rtc_info {
>
> struct regmap *regmap;
>
> + const struct max77686_rtc_driver_data *drv_data;
> +
> int virq;
> int rtc_24hr_mode;
> };
> @@ -72,12 +79,19 @@ enum MAX77686_RTC_OP {
> MAX77686_RTC_READ,
> };
>
> +static const struct max77686_rtc_driver_data max77686_drv_data = {
> + .delay = 16000,
> + .mask = 0x7f,
> +};
> +
> static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
> - int rtc_24hr_mode)
> + struct max77686_rtc_info *info)
> {
> - tm->tm_sec = data[RTC_SEC] & 0x7f;
> - tm->tm_min = data[RTC_MIN] & 0x7f;
> - if (rtc_24hr_mode)
> + u8 mask = info->drv_data->mask;
> +
> + tm->tm_sec = data[RTC_SEC] & mask;
> + tm->tm_min = data[RTC_MIN] & mask;
> + if (info->rtc_24hr_mode)
> tm->tm_hour = data[RTC_HOUR] & 0x1f;
> else {
> tm->tm_hour = data[RTC_HOUR] & 0x0f;
> @@ -86,10 +100,10 @@ static void max77686_rtc_data_to_tm(u8 *data, struct rtc_time *tm,
> }
>
> /* Only a single bit is set in data[], so fls() would be equivalent */
> - tm->tm_wday = ffs(data[RTC_WEEKDAY] & 0x7f) - 1;
> + tm->tm_wday = ffs(data[RTC_WEEKDAY] & mask) - 1;
> tm->tm_mday = data[RTC_DATE] & 0x1f;
> tm->tm_mon = (data[RTC_MONTH] & 0x0f) - 1;
> - tm->tm_year = (data[RTC_YEAR] & 0x7f) + 100;
> + tm->tm_year = (data[RTC_YEAR] & mask) + 100;
> tm->tm_yday = 0;
> tm->tm_isdst = 0;
> }
> @@ -117,6 +131,7 @@ static int max77686_rtc_update(struct max77686_rtc_info *info,
> {
> int ret;
> unsigned int data;
> + unsigned long delay = info->drv_data->delay;
>
> if (op == MAX77686_RTC_WRITE)
> data = 1 << RTC_UDR_SHIFT;
> @@ -129,9 +144,8 @@ static int max77686_rtc_update(struct max77686_rtc_info *info,
> dev_err(info->dev, "%s: fail to write update reg(ret=%d, data=0x%x)\n",
> __func__, ret, data);
> else {
> - /* Minimum 16ms delay required before RTC update. */
> - usleep_range(MAX77686_RTC_UPDATE_DELAY,
> - MAX77686_RTC_UPDATE_DELAY * 2);
> + /* Minimum delay required before RTC update. */
> + usleep_range(delay, delay * 2);
> }
>
> return ret;
> @@ -156,7 +170,7 @@ static int max77686_rtc_read_time(struct device *dev, struct rtc_time *tm)
> goto out;
> }
>
> - max77686_rtc_data_to_tm(data, tm, info->rtc_24hr_mode);
> + max77686_rtc_data_to_tm(data, tm, info);
>
> ret = rtc_valid_tm(tm);
>
> @@ -213,7 +227,7 @@ static int max77686_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
> goto out;
> }
>
> - max77686_rtc_data_to_tm(data, &alrm->time, info->rtc_24hr_mode);
> + max77686_rtc_data_to_tm(data, &alrm->time, info);
>
> alrm->enabled = 0;
> for (i = 0; i < ARRAY_SIZE(data); i++) {
> @@ -260,7 +274,7 @@ static int max77686_rtc_stop_alarm(struct max77686_rtc_info *info)
> goto out;
> }
>
> - max77686_rtc_data_to_tm(data, &tm, info->rtc_24hr_mode);
> + max77686_rtc_data_to_tm(data, &tm, info);
>
> for (i = 0; i < ARRAY_SIZE(data); i++)
> data[i] &= ~ALARM_ENABLE_MASK;
> @@ -299,7 +313,7 @@ static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
> goto out;
> }
>
> - max77686_rtc_data_to_tm(data, &tm, info->rtc_24hr_mode);
> + max77686_rtc_data_to_tm(data, &tm, info);
>
> data[RTC_SEC] |= (1 << ALARM_ENABLE_SHIFT);
> data[RTC_MIN] |= (1 << ALARM_ENABLE_SHIFT);
> @@ -307,7 +321,7 @@ static int max77686_rtc_start_alarm(struct max77686_rtc_info *info)
> data[RTC_WEEKDAY] &= ~ALARM_ENABLE_MASK;
> if (data[RTC_MONTH] & 0xf)
> data[RTC_MONTH] |= (1 << ALARM_ENABLE_SHIFT);
> - if (data[RTC_YEAR] & 0x7f)
> + if (data[RTC_YEAR] & info->drv_data->mask)
> data[RTC_YEAR] |= (1 << ALARM_ENABLE_SHIFT);
> if (data[RTC_DATE] & 0x1f)
> data[RTC_DATE] |= (1 << ALARM_ENABLE_SHIFT);
> @@ -423,6 +437,7 @@ static int max77686_rtc_probe(struct platform_device *pdev)
> {
> struct max77686_dev *max77686 = dev_get_drvdata(pdev->dev.parent);
> struct max77686_rtc_info *info;
> + const struct platform_device_id *id = platform_get_device_id(pdev);
> int ret;
>
> dev_info(&pdev->dev, "%s\n", __func__);
> @@ -436,6 +451,8 @@ static int max77686_rtc_probe(struct platform_device *pdev)
> info->dev = &pdev->dev;
> info->max77686 = max77686;
> info->rtc = max77686->rtc;
> + info->drv_data = (const struct max77686_rtc_driver_data *)
> + id->driver_data;
>
> platform_set_drvdata(pdev, info);
>
> @@ -510,7 +527,7 @@ static SIMPLE_DEV_PM_OPS(max77686_rtc_pm_ops,
> max77686_rtc_suspend, max77686_rtc_resume);
>
> static const struct platform_device_id rtc_id[] = {
> - { "max77686-rtc", 0 },
> + { "max77686-rtc", .driver_data = (kernel_ulong_t)&max77686_drv_data, },
> {},
> };
> MODULE_DEVICE_TABLE(platform, rtc_id);
> --
> 2.5.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists