Commit c55a8e24 authored by Cryolitia PukNgae's avatar Cryolitia PukNgae Committed by Guenter Roeck
Browse files

hwmon: (gpd-fan) initialize EC on driver load for Win 4 



The original implement will re-init the EC when it reports a zero
value, and it's a workaround for the black box buggy firmware.

Now a contributer test and report that, the bug is that, the firmware
won't initialize the EC on boot, so the EC ramains in unusable status.
And it won't need to re-init it during runtime. The original implement
is not perfect, any write command will be ignored until we first read
it. Just re-init it unconditionally when the driver load could work.

Fixes: 0ab88e23 ("hwmon: add GPD devices sensor driver")
Co-developed-by: default avatarkylon <3252255+kylon@users.noreply.github.com>
Signed-off-by: default avatarkylon <3252255+kylon@users.noreply.github.com>
Link: https://github.com/Cryolitia/gpd-fan-driver/pull/20


Signed-off-by: default avatarCryolitia PukNgae <cryolitia@uniontech.com>
Link: https://lore.kernel.org/r/20251030-win4-v1-1-c374dcb86985@uniontech.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 9efb297c

drivers/hwmon/gpd-fan.c

+25 −27
Original line number Diff line number Diff line
@@ -276,31 +276,6 @@ static int gpd_generic_read_rpm(void) 
	return (u16)high << 8 | low;

}



static void gpd_win4_init_ec(void)

{

	u8 chip_id, chip_ver;



	gpd_ecram_read(0x2000, &chip_id);



	if (chip_id == 0x55) {

		gpd_ecram_read(0x1060, &chip_ver);

		gpd_ecram_write(0x1060, chip_ver | 0x80);

	}

}



static int gpd_win4_read_rpm(void)

{

	int ret;



	ret = gpd_generic_read_rpm();



	if (ret == 0)

		// Re-init EC when speed is 0

		gpd_win4_init_ec();



	return ret;

}



static int gpd_wm2_read_rpm(void)

{

	for (u16 pwm_ctr_offset = GPD_PWM_CTR_OFFSET;
@@ -320,11 +295,10 @@ static int gpd_wm2_read_rpm(void) 
static int gpd_read_rpm(void)

{

	switch (gpd_driver_priv.drvdata->board) {

	case win4_6800u:

	case win_mini:

	case duo:

		return gpd_generic_read_rpm();

	case win4_6800u:

		return gpd_win4_read_rpm();

	case win_max_2:

		return gpd_wm2_read_rpm();

	}
@@ -607,6 +581,28 @@ static struct hwmon_chip_info gpd_fan_chip_info = { 
	.info = gpd_fan_hwmon_channel_info

};



static void gpd_win4_init_ec(void)

{

	u8 chip_id, chip_ver;



	gpd_ecram_read(0x2000, &chip_id);



	if (chip_id == 0x55) {

		gpd_ecram_read(0x1060, &chip_ver);

		gpd_ecram_write(0x1060, chip_ver | 0x80);

	}

}



static void gpd_init_ec(void)

{

	// The buggy firmware won't initialize EC properly on boot.

	// Before its initialization, reading RPM will always return 0,

	// and writing PWM will have no effect.

	// Initialize it manually on driver load.

	if (gpd_driver_priv.drvdata->board == win4_6800u)

		gpd_win4_init_ec();

}



static int gpd_fan_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;
@@ -634,6 +630,8 @@ static int gpd_fan_probe(struct platform_device *pdev) 
		return dev_err_probe(dev, PTR_ERR(hwdev),

				     "Failed to register hwmon device\n");



	gpd_init_ec();



	return 0;

}