[RFC PATCH 2/6] hwmon: axi-fan-control: add tacho devicetree properties
From: Nuno Sá <nuno.sa@analog.com>
Date: 2021-07-08 11:58:48
Also in:
linux-hwmon
Subsystem:
axi-fan-control hardware monitor driver, hardware monitoring, the rest · Maintainers:
Nuno Sá, Guenter Roeck, Linus Torvalds
This core is capable to run without any user interaction and when it does, it uses some predefined values in order to evaluate the tacho signal from the FAN. These values depend on the attached FAN, so that the core now exposes registers to change them accordingly. The values are: * adi,tacho-25-us: Expected tacho signal when the PWM is 25%; * adi,tacho-50-us: Expected tacho signal when the PWM is 50%; * adi,tacho-75-us: Expected tacho signal when the PWM is 75%; * adi,tacho-100-us: Expected tacho signal when the PWM is 100%. Signed-off-by: Nuno Sá <nuno.sa@analog.com> --- drivers/hwmon/axi-fan-control.c | 34 +++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+)
diff --git a/drivers/hwmon/axi-fan-control.c b/drivers/hwmon/axi-fan-control.c
index 901d1588234d..aa5a922f684d 100644
--- a/drivers/hwmon/axi-fan-control.c
+++ b/drivers/hwmon/axi-fan-control.c@@ -23,6 +23,14 @@ #define ADI_REG_PWM_PERIOD 0x00c0 #define ADI_REG_TACH_MEASUR 0x00c4 #define ADI_REG_TEMPERATURE 0x00c8 +#define ADI_REG_TACH_25 0x0140 +#define ADI_REG_TACH_50 0x0144 +#define ADI_REG_TACH_75 0x0148 +#define ADI_REG_TACH_100 0x014c +#define ADI_REG_TACH_25_TOL 0x0150 +#define ADI_REG_TACH_50_TOL 0x0154 +#define ADI_REG_TACH_75_TOL 0x0158 +#define ADI_REG_TACH_100_TOL 0x015c #define ADI_REG_IRQ_MASK 0x0040 #define ADI_REG_IRQ_PENDING 0x0044
@@ -328,6 +336,7 @@ static int axi_fan_control_init(struct axi_fan_control_data *ctl, const struct device_node *np) { int ret; + u32 tacho_val; /* get fan pulses per revolution */ ret = of_property_read_u32(np, "pulses-per-revolution", &ctl->ppr);
@@ -337,6 +346,31 @@ static int axi_fan_control_init(struct axi_fan_control_data *ctl, /* 1, 2 and 4 are the typical and accepted values */ if (ctl->ppr != 1 && ctl->ppr != 2 && ctl->ppr != 4) return -EINVAL; + + if (!of_property_read_u32(np, "adi,tacho-25-us", &tacho_val)) { + tacho_val = DIV_ROUND_CLOSEST_ULL((u64)tacho_val * ctl->clk_rate, 1000000); + axi_iowrite(tacho_val, ADI_REG_TACH_25, ctl); + axi_iowrite(DIV_ROUND_CLOSEST(tacho_val * 25, 100), ADI_REG_TACH_25_TOL, ctl); + } + + if (!of_property_read_u32(np, "adi,tacho-50-us", &tacho_val)) { + tacho_val = DIV_ROUND_CLOSEST_ULL((u64)tacho_val * ctl->clk_rate, 1000000); + axi_iowrite(tacho_val, ADI_REG_TACH_50, ctl); + axi_iowrite(DIV_ROUND_CLOSEST(tacho_val * 25, 100), ADI_REG_TACH_50_TOL, ctl); + } + + if (!of_property_read_u32(np, "adi,tacho-75-us", &tacho_val)) { + tacho_val = DIV_ROUND_CLOSEST_ULL((u64)tacho_val * ctl->clk_rate, 1000000); + axi_iowrite(tacho_val, ADI_REG_TACH_75, ctl); + axi_iowrite(DIV_ROUND_CLOSEST(tacho_val * 25, 100), ADI_REG_TACH_75_TOL, ctl); + } + + if (!of_property_read_u32(np, "adi,tacho-100-us", &tacho_val)) { + tacho_val = DIV_ROUND_CLOSEST_ULL((u64)tacho_val * ctl->clk_rate, 1000000); + axi_iowrite(tacho_val, ADI_REG_TACH_100, ctl); + axi_iowrite(DIV_ROUND_CLOSEST(tacho_val * 25, 100), ADI_REG_TACH_100_TOL, ctl); + } + /* * Enable all IRQs */
--
2.32.0