On Wed, Feb 13, 2019 at 11:43:29PM +0100, Hans de Goede wrote: > Hi, > > On 12-02-19 21:59, Yauhen Kharuzhy wrote: > > Add support for LEDs connected to the Intel Cherry Trail Whiskey Cove > > PMIC. Charger and general-purpose leds are supported. Hardware blinking > > is implemented, breathing is not. > > > > This driver was tested with Lenovo Yoga Book notebook. > > Thank you for working on this. The CHT Whiskey Cove PMIC is > also used on the GPD win and GPD pocket devices and there LED1 > by default indicates the charging status. > > Since your driver forces the LED into SWCTL mode on probe() > this means that any kernel with it enabled will break the > charging LEDs OOTB function, this is undesirable. > > I believe it would be best to add a custom "mode" attribute > to the led classdev, with "manual" and "on-when-charging" > modes, this would then control bits 0-1 of reg 0x5e1f and > by default these bits should be left as is when the driver > loads. > > Note that in my experience the "charging" mode only works > when bits 0-1 have the value 10. I've some written notes from > when I played with this myself and they say: > > -CHT WC powerled control 0x5e1f: bits 0-1: > 0: ???? > 1: Off > 2: On when charging > 3: On > -CHT WC powerled pattern control 0x5e20: bits 1-2: > 0: Off > 1: On > 2: Blinking > 3: Glowing Maybe you are right, I will check but at Linux Yoga Book this LED doesn't work as HW-controlled charging status indicator, so I didn't discovery this. I used this source as reference; https://github.com/jekhor/yogabook-linux-android-kernel/blob/cm-13.0/drivers/misc/charger_gp_led.c > Also note that the 0x5e20 notes do not match with your > defines, I believe this is a small bug in your code, see > comments in line below. > > As for the 0x5e20 settings, I believe another custom > sysfs attribute, called "breathing" would be a good idea to > export the breathing functionality. > > The way I see this working is that writing "1" to this will > turn on glowing mode, and writing 0 to it, or 0 to brightness > will turn it off. Reading it will return 1/0 depending on > whether the LED is in glowing mode or not. Jacek? Pavel? I thought about pattern_set() implementation for 'breathing' mode in future but this doesn't seem simple, maybe custom attribute will has sense? > > For an example of adding custom sysfs attributes to a > led-class device see kbd_led_groups and kbd_led_attrs in: > drivers/platform/x86/dell-laptop.c > > > + > > +#define CHT_WC_LED1_CTRL 0x5e1f > > +#define CHT_WC_LED1_FSM 0x5e20 > > +#define CHT_WC_LED1_PWM 0x5e21 > > + > > +#define CHT_WC_LED2_CTRL 0x4fdf > > +#define CHT_WC_LED2_FSM 0x4fe0 > > +#define CHT_WC_LED2_PWM 0x4fe1 > > + > > +/* HW or SW control of charging led */ > > +#define CHT_WC_LED1_SWCTL BIT(0) > > +#define CHT_WC_LED1_ON BIT(1) > > + > > +#define CHT_WC_LED2_ON BIT(0) > > +#define CHT_WC_LED_I_MA2_5 (2 << 2) > > +/* LED current limit */ > > +#define CHT_WC_LED_I_MASK GENMASK(3, 2) > > + > > +#define CHT_WC_LED_F_1_4_HZ (0 << 4) > > +#define CHT_WC_LED_F_1_2_HZ (1 << 4) > > +#define CHT_WC_LED_F_1_HZ (2 << 4) > > +#define CHT_WC_LED_F_2_HZ (3 << 4) > > +#define CHT_WC_LED_F_MASK 0x30 > > + > > +#define CHT_WC_LED_EFF_ON BIT(1) > > +#define CHT_WC_LED_EFF_BLINKING BIT(2) > > +#define CHT_WC_LED_EFF_BREATHING BIT(3) > > +#define CHT_WC_LED_EFF_MASK 0x06 > > So your MASK is correct here, but the values used should > be based on that, so you get: > > #define CHT_WC_LED_EFF_ON (1 << 1) > #define CHT_WC_LED_EFF_BLINKING (2 << 1) > #define CHT_WC_LED_EFF_BREATHING (3 << 1) > > Note that this effectively only changes the value of > CHT_WC_LED_EFF_BREATHING, so that it now to fits in your > mask. > > Regards, Hm, it seems lost in refactoring time, thanks. My original defines were: #define CHT_WC_LED_EFF_ON (1<<1) #define CHT_WC_LED_EFF_BLINKING (2<<1) #define CHT_WC_LED_EFF_BREATHING (3<<1) #define CHT_WC_LED_EFF_MASK 0x06 I will revert this in next version. -- Yauhen Kharuzhy
