[v6,07/10] pwm: dwc: make timer clock configurable
Commit Message
Add a configurable clock base rate for the pwm as when being built
for non-PCI the block may be sourced from an internal clock.
Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
---
v6:
- removed DWC_CLK_PERIOD_NS as it is now not needed
v4:
- moved earlier before the of changes to make the of changes one patch
v2:
- removed the ifdef and merged the other clock patch in here
---
drivers/pwm/pwm-dwc-pci.c | 1 +
drivers/pwm/pwm-dwc.c | 10 ++++++----
drivers/pwm/pwm-dwc.h | 3 ++-
3 files changed, 9 insertions(+), 5 deletions(-)
Comments
Hello,
On Thu, Oct 20, 2022 at 04:16:07PM +0100, Ben Dooks wrote:
> Add a configurable clock base rate for the pwm as when being built
> for non-PCI the block may be sourced from an internal clock.
>
> Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
> ---
> v6:
> - removed DWC_CLK_PERIOD_NS as it is now not needed
> v4:
> - moved earlier before the of changes to make the of changes one patch
> v2:
> - removed the ifdef and merged the other clock patch in here
> ---
> drivers/pwm/pwm-dwc-pci.c | 1 +
> drivers/pwm/pwm-dwc.c | 10 ++++++----
> drivers/pwm/pwm-dwc.h | 3 ++-
> 3 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/pwm/pwm-dwc-pci.c b/drivers/pwm/pwm-dwc-pci.c
> index 2213d0e7f3c8..949423e368f9 100644
> --- a/drivers/pwm/pwm-dwc-pci.c
> +++ b/drivers/pwm/pwm-dwc-pci.c
> @@ -20,6 +20,7 @@
> #include <linux/pci.h>
> #include <linux/pm_runtime.h>
> #include <linux/pwm.h>
> +#include <linux/clk.h>
>
> #include "pwm-dwc.h"
>
I assume this is only needed because pwm-dwc.h now uses struct clk.
Maybe just add
struct clk;
to the pwm-dwc.h instead of this hunk?
> [...]
> diff --git a/drivers/pwm/pwm-dwc.h b/drivers/pwm/pwm-dwc.h
> index 68f98eb76152..dc451cb2eff5 100644
> --- a/drivers/pwm/pwm-dwc.h
> +++ b/drivers/pwm/pwm-dwc.h
> @@ -22,7 +22,6 @@
> #define DWC_TIMERS_COMP_VERSION 0xac
>
> #define DWC_TIMERS_TOTAL 8
> -#define DWC_CLK_PERIOD_NS 10
>
> /* Timer Control Register */
> #define DWC_TIM_CTRL_EN BIT(0)
> @@ -41,6 +40,8 @@ struct dwc_pwm_ctx {
> struct dwc_pwm {
> struct pwm_chip chip;
> void __iomem *base;
> + struct clk *clk;
This is unsed, please add it in the patch that makes use of it.
> + unsigned int clk_ns;
> struct dwc_pwm_ctx ctx[DWC_TIMERS_TOTAL];
> };
> #define to_dwc_pwm(p) (container_of((p), struct dwc_pwm, chip))
Best regards
Uwe
@@ -20,6 +20,7 @@
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/pwm.h>
+#include <linux/clk.h>
#include "pwm-dwc.h"
@@ -14,6 +14,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <linux/pwm.h>
@@ -47,13 +48,13 @@ static int __dwc_pwm_configure_timer(struct dwc_pwm *dwc,
* periods and check are the result within HW limits between 1 and
* 2^32 periods.
*/
- tmp = DIV_ROUND_CLOSEST_ULL(state->duty_cycle, DWC_CLK_PERIOD_NS);
+ tmp = DIV_ROUND_CLOSEST_ULL(state->duty_cycle, dwc->clk_ns);
if (tmp < 1 || tmp > (1ULL << 32))
return -ERANGE;
low = tmp - 1;
tmp = DIV_ROUND_CLOSEST_ULL(state->period - state->duty_cycle,
- DWC_CLK_PERIOD_NS);
+ dwc->clk_ns);
if (tmp < 1 || tmp > (1ULL << 32))
return -ERANGE;
high = tmp - 1;
@@ -128,12 +129,12 @@ static void dwc_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
duty = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(pwm->hwpwm));
duty += 1;
- duty *= DWC_CLK_PERIOD_NS;
+ duty *= dwc->clk_ns;
state->duty_cycle = duty;
period = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(pwm->hwpwm));
period += 1;
- period *= DWC_CLK_PERIOD_NS;
+ period *= dwc->clk_ns;
period += duty;
state->period = period;
@@ -156,6 +157,7 @@ struct dwc_pwm *dwc_pwm_alloc(struct device *dev)
if (!dwc)
return NULL;
+ dwc->clk_ns = 10;
dwc->chip.dev = dev;
dwc->chip.ops = &dwc_pwm_ops;
dwc->chip.npwm = DWC_TIMERS_TOTAL;
@@ -22,7 +22,6 @@
#define DWC_TIMERS_COMP_VERSION 0xac
#define DWC_TIMERS_TOTAL 8
-#define DWC_CLK_PERIOD_NS 10
/* Timer Control Register */
#define DWC_TIM_CTRL_EN BIT(0)
@@ -41,6 +40,8 @@ struct dwc_pwm_ctx {
struct dwc_pwm {
struct pwm_chip chip;
void __iomem *base;
+ struct clk *clk;
+ unsigned int clk_ns;
struct dwc_pwm_ctx ctx[DWC_TIMERS_TOTAL];
};
#define to_dwc_pwm(p) (container_of((p), struct dwc_pwm, chip))