Introduce apply in pwm_ops to replace legacy operations, like enable, disable, config and set_polarity.
Signed-off-by: Song Chen chensong_2000@189.cn
--- V2: 1, define duty_cycle and period as u64 in gb_pwm_config_operation. 2, define duty and period as u64 in gb_pwm_config_request. 3, disable before configuring duty and period if the eventual goal is a disabled state. --- drivers/staging/greybus/pwm.c | 61 ++++++++++++----------- include/linux/greybus/greybus_protocols.h | 4 +- 2 files changed, 34 insertions(+), 31 deletions(-)
diff --git a/drivers/staging/greybus/pwm.c b/drivers/staging/greybus/pwm.c index 891a6a672378..03c69db5b9be 100644 --- a/drivers/staging/greybus/pwm.c +++ b/drivers/staging/greybus/pwm.c @@ -89,7 +89,7 @@ static int gb_pwm_deactivate_operation(struct gb_pwm_chip *pwmc, }
static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc, - u8 which, u32 duty, u32 period) + u8 which, u64 duty, u64 period) { struct gb_pwm_config_request request; struct gbphy_device *gbphy_dev; @@ -99,8 +99,8 @@ static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc, return -EINVAL;
request.which = which; - request.duty = cpu_to_le32(duty); - request.period = cpu_to_le32(period); + request.duty = duty; + request.period = period;
gbphy_dev = to_gbphy_dev(pwmc->chip.dev); ret = gbphy_runtime_get_sync(gbphy_dev); @@ -204,43 +204,46 @@ static void gb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) gb_pwm_deactivate_operation(pwmc, pwm->hwpwm); }
-static int gb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, - int duty_ns, int period_ns) +static int gb_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) { + int err; + bool enabled = pwm->state.enabled; struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- return gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_ns, period_ns); -}; - -static int gb_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, - enum pwm_polarity polarity) -{ - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip); - - return gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, polarity); -}; + /* set polarity */ + if (state->polarity != pwm->state.polarity) { + if (enabled) { + gb_pwm_disable_operation(pwmc, pwm->hwpwm); + enabled = false; + } + err = gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, state->polarity); + if (err) + return err; + }
-static int gb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip); + if (!state->enabled) { + if (enabled) + gb_pwm_disable_operation(pwmc, pwm->hwpwm); + return 0; + }
- return gb_pwm_enable_operation(pwmc, pwm->hwpwm); -}; + /* set period and duty cycle*/ + err = gb_pwm_config_operation(pwmc, pwm->hwpwm, state->duty_cycle, state->period); + if (err) + return err;
-static void gb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) -{ - struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip); + /* enable/disable */ + if (!enabled) + return gb_pwm_enable_operation(pwmc, pwm->hwpwm);
- gb_pwm_disable_operation(pwmc, pwm->hwpwm); -}; + return 0; +}
static const struct pwm_ops gb_pwm_ops = { .request = gb_pwm_request, .free = gb_pwm_free, - .config = gb_pwm_config, - .set_polarity = gb_pwm_set_polarity, - .enable = gb_pwm_enable, - .disable = gb_pwm_disable, + .apply = gb_pwm_apply, .owner = THIS_MODULE, };
diff --git a/include/linux/greybus/greybus_protocols.h b/include/linux/greybus/greybus_protocols.h index aeb8f9243545..81a6f16de098 100644 --- a/include/linux/greybus/greybus_protocols.h +++ b/include/linux/greybus/greybus_protocols.h @@ -812,8 +812,8 @@ struct gb_pwm_deactivate_request {
struct gb_pwm_config_request { __u8 which; - __le32 duty; - __le32 period; + __u64 duty; + __u64 period; } __packed;
struct gb_pwm_polarity_request {
On Fri, Feb 11, 2022 at 08:02:27PM +0800, Song Chen wrote:
Introduce apply in pwm_ops to replace legacy operations, like enable, disable, config and set_polarity.
Signed-off-by: Song Chen chensong_2000@189.cn
V2: 1, define duty_cycle and period as u64 in gb_pwm_config_operation. 2, define duty and period as u64 in gb_pwm_config_request. 3, disable before configuring duty and period if the eventual goal is a disabled state.
drivers/staging/greybus/pwm.c | 61 ++++++++++++----------- include/linux/greybus/greybus_protocols.h | 4 +- 2 files changed, 34 insertions(+), 31 deletions(-)
diff --git a/drivers/staging/greybus/pwm.c b/drivers/staging/greybus/pwm.c index 891a6a672378..03c69db5b9be 100644 --- a/drivers/staging/greybus/pwm.c +++ b/drivers/staging/greybus/pwm.c @@ -89,7 +89,7 @@ static int gb_pwm_deactivate_operation(struct gb_pwm_chip *pwmc, } static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc,
u8 which, u32 duty, u32 period)
u8 which, u64 duty, u64 period){ struct gb_pwm_config_request request; struct gbphy_device *gbphy_dev; @@ -99,8 +99,8 @@ static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc, return -EINVAL; request.which = which;
- request.duty = cpu_to_le32(duty);
- request.period = cpu_to_le32(period);
- request.duty = duty;
- request.period = period;
gbphy_dev = to_gbphy_dev(pwmc->chip.dev); ret = gbphy_runtime_get_sync(gbphy_dev); @@ -204,43 +204,46 @@ static void gb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) gb_pwm_deactivate_operation(pwmc, pwm->hwpwm); } -static int gb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)+static int gb_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state){
- int err;
- bool enabled = pwm->state.enabled; struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- return gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_ns, period_ns);
-};
-static int gb_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
enum pwm_polarity polarity)-{
- struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- return gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, polarity);
-};
- /* set polarity */
- if (state->polarity != pwm->state.polarity) {
if (enabled) {gb_pwm_disable_operation(pwmc, pwm->hwpwm);enabled = false;}err = gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, state->polarity);if (err)return err;- }
-static int gb_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) -{
- struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- if (!state->enabled) {
if (enabled)gb_pwm_disable_operation(pwmc, pwm->hwpwm);return 0;- }
- return gb_pwm_enable_operation(pwmc, pwm->hwpwm);
-};
- /* set period and duty cycle*/
- err = gb_pwm_config_operation(pwmc, pwm->hwpwm, state->duty_cycle, state->period);
- if (err)
return err;-static void gb_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) -{
- struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- /* enable/disable */
- if (!enabled)
return gb_pwm_enable_operation(pwmc, pwm->hwpwm);
- gb_pwm_disable_operation(pwmc, pwm->hwpwm);
-};
- return 0;
+} static const struct pwm_ops gb_pwm_ops = { .request = gb_pwm_request, .free = gb_pwm_free,
- .config = gb_pwm_config,
- .set_polarity = gb_pwm_set_polarity,
- .enable = gb_pwm_enable,
- .disable = gb_pwm_disable,
- .apply = gb_pwm_apply, .owner = THIS_MODULE,
}; diff --git a/include/linux/greybus/greybus_protocols.h b/include/linux/greybus/greybus_protocols.h index aeb8f9243545..81a6f16de098 100644 --- a/include/linux/greybus/greybus_protocols.h +++ b/include/linux/greybus/greybus_protocols.h @@ -812,8 +812,8 @@ struct gb_pwm_deactivate_request { struct gb_pwm_config_request { __u8 which;
- __le32 duty;
- __le32 period;
- __u64 duty;
- __u64 period;
} __packed;
Did you just change a greybus protocol message that is sent over the wire? Why? And why drop the endian marking of it?
Are you sure this is ok?
thanks,
greg k-h
Hello,
orthogonal to the feedback you got for the protocol part, here some thoughts to the PWM specific bits;
On Fri, Feb 11, 2022 at 08:02:27PM +0800, Song Chen wrote:
Introduce apply in pwm_ops to replace legacy operations, like enable, disable, config and set_polarity.
Signed-off-by: Song Chen chensong_2000@189.cn
V2: 1, define duty_cycle and period as u64 in gb_pwm_config_operation. 2, define duty and period as u64 in gb_pwm_config_request. 3, disable before configuring duty and period if the eventual goal is a disabled state.
drivers/staging/greybus/pwm.c | 61 ++++++++++++----------- include/linux/greybus/greybus_protocols.h | 4 +- 2 files changed, 34 insertions(+), 31 deletions(-)
diff --git a/drivers/staging/greybus/pwm.c b/drivers/staging/greybus/pwm.c index 891a6a672378..03c69db5b9be 100644 --- a/drivers/staging/greybus/pwm.c +++ b/drivers/staging/greybus/pwm.c @@ -89,7 +89,7 @@ static int gb_pwm_deactivate_operation(struct gb_pwm_chip *pwmc, } static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc,
u8 which, u32 duty, u32 period)
u8 which, u64 duty, u64 period){ struct gb_pwm_config_request request; struct gbphy_device *gbphy_dev; @@ -99,8 +99,8 @@ static int gb_pwm_config_operation(struct gb_pwm_chip *pwmc, return -EINVAL; request.which = which;
- request.duty = cpu_to_le32(duty);
- request.period = cpu_to_le32(period);
- request.duty = duty;
- request.period = period;
If you don't change the wire protocol, you want something like:
if (period > U32_MAX) period = U32_MAX;
if (duty > period) duty = period;
To further improve the PWM driver it would be great if you added a paragraph about the details of its behaviour; in the format the other drivers do that (see e.g. drivers/pwm/pwm-sifive.c). It should describe the following properties:
- Is a period completed when period/duty changes? - Is a period completed when the hardware is disabled? - How does the output behave on disable?
In this specific case I think there is also some rounding behaviour in the backend?! If so, describing this would be good, too.
gbphy_dev = to_gbphy_dev(pwmc->chip.dev); ret = gbphy_runtime_get_sync(gbphy_dev); @@ -204,43 +204,46 @@ static void gb_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) gb_pwm_deactivate_operation(pwmc, pwm->hwpwm); } -static int gb_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)+static int gb_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
const struct pwm_state *state){
- int err;
- bool enabled = pwm->state.enabled; struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- return gb_pwm_config_operation(pwmc, pwm->hwpwm, duty_ns, period_ns);
-};
-static int gb_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
enum pwm_polarity polarity)-{
- struct gb_pwm_chip *pwmc = pwm_chip_to_gb_pwm_chip(chip);
- return gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, polarity);
-};
- /* set polarity */
- if (state->polarity != pwm->state.polarity) {
if (enabled) {gb_pwm_disable_operation(pwmc, pwm->hwpwm);enabled = false;}err = gb_pwm_set_polarity_operation(pwmc, pwm->hwpwm, state->polarity);if (err)return err;- }
This is copied from the legacy pwm handling in the pwm core. This is good in principle. But if your hardware can change polarity without stopping operation, that would be the thing to do. (The pwm core cannot assume this, so it doesn't.)
Best regards Uwe
-
Greg KH -
Song Chen -
Uwe Kleine-König