An updated set of patches for the Designware PWM driver
split into PCI and OF versions. I think I got all the
review issues in this set.
Sorry for the delay in getting this out, between conferences
and other absences there has been little time to deal with
this set. I will be now out of office until 3rd Jan 2023.
v7:
- fixup kconfig from previous pcie changes
- re-order kconfig to make dwc core be selected by PCI driver
- move clk variable to patch it is used in
v6:
- fix removal ordering of DWC_PERIOD_NS
v5:
- fixed kconfig string error
- merged pwm-nr into main of code
- split of code from pci code
- updated pwm-nr capping
- fix duplicate error reporting in of-code
- fix return in of-probe
- remove unecessary remove function as devm_ functions sort this
- fixed ordering of properties
- added missing reg item
- fixed missing split of the two clock sources.
- get bus clock in of code
v4:
- split pci and of into new modules
- fixup review comments
- fix typos in dt-bindings
v3:
- change the compatible name
- squash down pwm count patch
- fixup patch naming
v2:
- fix #pwm-cells count to be 3
- fix indetation
- merge the two clock patches
- add HAS_IOMEM as a config dependency
Ben Dooks (10):
dt-bindings: pwm: Document Synopsys DesignWare
snps,pwm-dw-apb-timers-pwm2
pwm: dwc: allow driver to be built with COMPILE_TEST
pwm: dwc: change &pci->dev to dev in probe
pwm: dwc: move memory alloc to own function
pwm: dwc: use devm_pwmchip_add
pwm: dwc: split pci out of core driver
pwm: dwc: make timer clock configurable
pwm: dwc: add of/platform support
pwm: dwc: add PWM bit unset in get_state call
pwm: dwc: use clock rate in hz to avoid rounding issues
.../bindings/pwm/snps,dw-apb-timers-pwm2.yaml | 68 ++++++
drivers/pwm/Kconfig | 26 ++-
drivers/pwm/Makefile | 2 +
drivers/pwm/pwm-dwc-of.c | 76 +++++++
drivers/pwm/pwm-dwc-pci.c | 134 +++++++++++
drivers/pwm/pwm-dwc.c | 210 ++++--------------
drivers/pwm/pwm-dwc.h | 59 +++++
7 files changed, 404 insertions(+), 171 deletions(-)
create mode 100644 Documentation/devicetree/bindings/pwm/snps,dw-apb-timers-pwm2.yaml
create mode 100644 drivers/pwm/pwm-dwc-of.c
create mode 100644 drivers/pwm/pwm-dwc-pci.c
create mode 100644 drivers/pwm/pwm-dwc.h
--
2.35.1
If we are not in PWM mode, then the output is technically a 50%
output based on a single timer instead of the high-low based on
the two counters. Add a check for the PWM mode in dwc_pwm_get_state()
and if DWC_TIM_CTRL_PWM is not set, then return a 50% cycle.
This may only be an issue on initialisation, as the rest of the
code currently assumes we're always going to have the extended
PWM mode using two counters.
Signed-off-by: Ben Dooks <[email protected]>
---
v4:
- fixed review comment on mulit-line calculations
---
drivers/pwm/pwm-dwc.c | 29 ++++++++++++++++++-----------
1 file changed, 18 insertions(+), 11 deletions(-)
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index 1251620ab771..5ef0fe7ea3e9 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -121,23 +121,30 @@ static void dwc_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
{
struct dwc_pwm *dwc = to_dwc_pwm(chip);
u64 duty, period;
+ u32 ctrl, ld, ld2;
pm_runtime_get_sync(chip->dev);
- state->enabled = !!(dwc_pwm_readl(dwc,
- DWC_TIM_CTRL(pwm->hwpwm)) & DWC_TIM_CTRL_EN);
+ ctrl = dwc_pwm_readl(dwc, DWC_TIM_CTRL(pwm->hwpwm));
+ ld = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(pwm->hwpwm));
+ ld2 = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(pwm->hwpwm));
- duty = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(pwm->hwpwm));
- duty += 1;
- duty *= dwc->clk_ns;
- state->duty_cycle = duty;
+ state->enabled = !!(ctrl & DWC_TIM_CTRL_EN);
- period = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(pwm->hwpwm));
- period += 1;
- period *= dwc->clk_ns;
- period += duty;
- state->period = period;
+ /* If we're not in PWM, technically the output is a 50-50
+ * based on the timer load-count only.
+ */
+ if (ctrl & DWC_TIM_CTRL_PWM) {
+ duty = (ld + 1) * dwc->clk_ns;
+ period = (ld2 + 1) * dwc->clk_ns;
+ period += duty;
+ } else {
+ duty = (ld + 1) * dwc->clk_ns;
+ period = duty * 2;
+ }
+ state->period = period;
+ state->duty_cycle = duty;
state->polarity = PWM_POLARITY_INVERSED;
pm_runtime_put_sync(chip->dev);
--
2.35.1
The dwc pwm controller can be used in non-PCI systems, so allow
either platform or OF based probing.
Signed-off-by: Ben Dooks <[email protected]>
---
v7:
- fixup kconfig from previous pcie changes
v5:
- fix missing " in kconfig
- remove .remove method, devm already sorts this.
- merge pwm-number code
- split the of code out of the core
- get bus clock
v4:
- moved the compile test code earlier
- fixed review comments
- used NS_PER_SEC
- use devm_clk_get_enabled
- ensure we get the bus clock
v3:
- changed compatible name
fixup add pwm/Kconfig
fixup: kconfig change for of addition
---
drivers/pwm/Kconfig | 10 ++++++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-dwc-of.c | 76 +++++++++++++++++++++++++++++++++++++++
drivers/pwm/pwm-dwc-pci.c | 1 +
drivers/pwm/pwm-dwc.c | 1 +
drivers/pwm/pwm-dwc.h | 1 +
6 files changed, 90 insertions(+)
create mode 100644 drivers/pwm/pwm-dwc-of.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 8c5ef388a981..74ab526e8b8c 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -193,6 +193,16 @@ config PWM_DWC
To compile this driver as a module, choose M here: the module
will be called pwm-dwc-pci.
+config PWM_DWC_OF
+ tristate "DesignWare PWM Controller (OF bus)"
+ depends on HAS_IOMEM && OF
+ select PWM_DWC_CORE
+ help
+ PWM driver for Synopsys DWC PWM Controller on an OF bus.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-dwc-of.
+
config PWM_EP93XX
tristate "Cirrus Logic EP93xx PWM support"
depends on ARCH_EP93XX || COMPILE_TEST
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index a70d36623129..d1fd1641f077 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o
obj-$(CONFIG_PWM_CRC) += pwm-crc.o
obj-$(CONFIG_PWM_CROS_EC) += pwm-cros-ec.o
obj-$(CONFIG_PWM_DWC) += pwm-dwc.o
+obj-$(CONFIG_PWM_DWC_OF) += pwm-dwc-of.o
obj-$(CONFIG_PWM_DWC_PCI) += pwm-dwc-pci.o
obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o
obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o
diff --git a/drivers/pwm/pwm-dwc-of.c b/drivers/pwm/pwm-dwc-of.c
new file mode 100644
index 000000000000..c5b4351cc7b0
--- /dev/null
+++ b/drivers/pwm/pwm-dwc-of.c
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DesignWare PWM Controller driver OF
+ *
+ * Copyright (C) 2022 SiFive, Inc.
+ */
+
+#include <linux/bitops.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+#include <linux/io.h>
+
+#include "pwm-dwc.h"
+
+static int dwc_pwm_plat_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct dwc_pwm *dwc;
+ struct clk *bus;
+ u32 nr_pwm;
+
+ dwc = dwc_pwm_alloc(dev);
+ if (!dwc)
+ return -ENOMEM;
+
+ if (!device_property_read_u32(dev, "snps,pwm-number", &nr_pwm)) {
+ if (nr_pwm > DWC_TIMERS_TOTAL)
+ dev_err(dev, "too many PWMs (%d) specified, capping at %d\n",
+ nr_pwm, dwc->chip.npwm);
+ else
+ dwc->chip.npwm = nr_pwm;
+ }
+
+ dwc->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(dwc->base))
+ return PTR_ERR(dwc->base);
+
+ bus = devm_clk_get_enabled(dev, NULL);
+ if (IS_ERR(bus))
+ return dev_err_probe(dev, PTR_ERR(bus),
+ "failed to get clock\n");
+
+ dwc->clk = devm_clk_get_enabled(dev, "timer");
+ if (IS_ERR(dwc->clk))
+ return dev_err_probe(dev, PTR_ERR(dwc->clk),
+ "failed to get timer clock\n");
+
+ dwc->clk_ns = NSEC_PER_SEC / clk_get_rate(dwc->clk);
+ return devm_pwmchip_add(dev, &dwc->chip);
+}
+
+static const struct of_device_id dwc_pwm_dt_ids[] = {
+ { .compatible = "snps,dw-apb-timers-pwm2" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, dwc_pwm_dt_ids);
+
+static struct platform_driver dwc_pwm_plat_driver = {
+ .driver = {
+ .name = "dwc-pwm",
+ .of_match_table = dwc_pwm_dt_ids,
+ },
+ .probe = dwc_pwm_plat_probe,
+};
+
+module_platform_driver(dwc_pwm_plat_driver);
+
+MODULE_ALIAS("platform:dwc-pwm-of");
+MODULE_AUTHOR("Ben Dooks <[email protected]>");
+MODULE_DESCRIPTION("DesignWare PWM Controller");
+MODULE_LICENSE("GPL");
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"
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index 0c6beafa8c41..1251620ab771 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -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>
diff --git a/drivers/pwm/pwm-dwc.h b/drivers/pwm/pwm-dwc.h
index b29d8cd21208..dc451cb2eff5 100644
--- a/drivers/pwm/pwm-dwc.h
+++ b/drivers/pwm/pwm-dwc.h
@@ -40,6 +40,7 @@ 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];
};
--
2.35.1
Allow dwc driver to be built with COMPILE_TEST should allow
better coverage when build testing.
Signed-off-by: Ben Dooks <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
---
v4:
- moved to earlier in the series
v3:
- add HAS_IOMEM depdency for compile testing
---
drivers/pwm/Kconfig | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 60d13a949bc5..3f3c53af4a56 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -176,7 +176,8 @@ config PWM_CROS_EC
config PWM_DWC
tristate "DesignWare PWM Controller"
- depends on PCI
+ depends on PCI || COMPILE_TEST
+ depends on HAS_IOMEM
help
PWM driver for Synopsys DWC PWM Controller attached to a PCI bus.
--
2.35.1
The dwc_pwm_probe() assignes dev to be &pci->dev but then uses
&pci->dev throughout the function. Change these all to the be
'dev' variable to make lines shorter.
Signed-off-by: Ben Dooks <[email protected]>
Acked-by: Uwe Kleine-König <[email protected]>
---
drivers/pwm/pwm-dwc.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index 7568300bb11e..c706ef9a7ba1 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -202,14 +202,13 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
struct dwc_pwm *dwc;
int ret;
- dwc = devm_kzalloc(&pci->dev, sizeof(*dwc), GFP_KERNEL);
+ dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
if (!dwc)
return -ENOMEM;
ret = pcim_enable_device(pci);
if (ret) {
- dev_err(&pci->dev,
- "Failed to enable device (%pe)\n", ERR_PTR(ret));
+ dev_err(dev, "Failed to enable device (%pe)\n", ERR_PTR(ret));
return ret;
}
@@ -217,14 +216,13 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
ret = pcim_iomap_regions(pci, BIT(0), pci_name(pci));
if (ret) {
- dev_err(&pci->dev,
- "Failed to iomap PCI BAR (%pe)\n", ERR_PTR(ret));
+ dev_err(dev, "Failed to iomap PCI BAR (%pe)\n", ERR_PTR(ret));
return ret;
}
dwc->base = pcim_iomap_table(pci)[0];
if (!dwc->base) {
- dev_err(&pci->dev, "Base address missing\n");
+ dev_err(dev, "Base address missing\n");
return -ENOMEM;
}
--
2.35.1
In preparation for adding other bus support, move the allocation
of the pwm struct out of the main driver code.
Signed-off-by: Ben Dooks <[email protected]>
---
drivers/pwm/pwm-dwc.c | 24 +++++++++++++++++-------
1 file changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index c706ef9a7ba1..61f11e0a9319 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -196,13 +196,29 @@ static const struct pwm_ops dwc_pwm_ops = {
.owner = THIS_MODULE,
};
+static struct dwc_pwm *dwc_pwm_alloc(struct device *dev)
+{
+ struct dwc_pwm *dwc;
+
+ dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
+ if (!dwc)
+ return NULL;
+
+ dwc->chip.dev = dev;
+ dwc->chip.ops = &dwc_pwm_ops;
+ dwc->chip.npwm = DWC_TIMERS_TOTAL;
+
+ dev_set_drvdata(dev, dwc);
+ return dwc;
+}
+
static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
{
struct device *dev = &pci->dev;
struct dwc_pwm *dwc;
int ret;
- dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
+ dwc = dwc_pwm_alloc(dev);
if (!dwc)
return -ENOMEM;
@@ -226,12 +242,6 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
return -ENOMEM;
}
- pci_set_drvdata(pci, dwc);
-
- dwc->chip.dev = dev;
- dwc->chip.ops = &dwc_pwm_ops;
- dwc->chip.npwm = DWC_TIMERS_TOTAL;
-
ret = pwmchip_add(&dwc->chip);
if (ret)
return ret;
--
2.35.1
On 23/12/2022 15:38, Ben Dooks wrote:
> An updated set of patches for the Designware PWM driver
> split into PCI and OF versions. I think I got all the
> review issues in this set.
>
> Sorry for the delay in getting this out, between conferences
> and other absences there has been little time to deal with
> this set. I will be now out of office until 3rd Jan 2023.
Hi, how's the progress on review and getting this set finalised?
Hello Ben,
On Tue, Jan 17, 2023 at 04:39:34PM +0000, Ben Dooks wrote:
> On 23/12/2022 15:38, Ben Dooks wrote:
> > An updated set of patches for the Designware PWM driver
> > split into PCI and OF versions. I think I got all the
> > review issues in this set.
> >
> > Sorry for the delay in getting this out, between conferences
> > and other absences there has been little time to deal with
> > this set. I will be now out of office until 3rd Jan 2023.
>
> Hi, how's the progress on review and getting this set finalised?
Speaking for me:
Your patch set isn't forgotton. It's just that my time is limited and
reviewing a new driver is time intensive.
I'm sorry I cannot give feedback in a more timely manner, but I will
come to it eventually.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
On Fri, Dec 23, 2022 at 03:38:14PM +0000, Ben Dooks wrote:
> In preparation for adding other bus support, move the allocation
> of the pwm struct out of the main driver code.
>
> Signed-off-by: Ben Dooks <[email protected]>
> ---
> drivers/pwm/pwm-dwc.c | 24 +++++++++++++++++-------
> 1 file changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
> index c706ef9a7ba1..61f11e0a9319 100644
> --- a/drivers/pwm/pwm-dwc.c
> +++ b/drivers/pwm/pwm-dwc.c
> @@ -196,13 +196,29 @@ static const struct pwm_ops dwc_pwm_ops = {
> .owner = THIS_MODULE,
> };
>
> +static struct dwc_pwm *dwc_pwm_alloc(struct device *dev)
> +{
> + struct dwc_pwm *dwc;
> +
> + dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
> + if (!dwc)
> + return NULL;
> +
> + dwc->chip.dev = dev;
> + dwc->chip.ops = &dwc_pwm_ops;
> + dwc->chip.npwm = DWC_TIMERS_TOTAL;
> +
> + dev_set_drvdata(dev, dwc);
I don't particularily like that this dev_set_drvdata is matched by
pci_get_drvdata in .remove(), but this isn't going to break I guess. So:
Acked-by: Uwe Kleine-K?nig <[email protected]>
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
On Fri, 23 Dec 2022 15:38:10 +0000, Ben Dooks wrote:
> An updated set of patches for the Designware PWM driver
> split into PCI and OF versions. I think I got all the
> review issues in this set.
>
> Sorry for the delay in getting this out, between conferences
> and other absences there has been little time to deal with
> this set. I will be now out of office until 3rd Jan 2023.
>
> [...]
Applied, thanks!
[01/10] dt-bindings: pwm: Document Synopsys DesignWare snps,pwm-dw-apb-timers-pwm2
commit: 0f03bf300833c05d914ab7f5ab3d8bc8564e9912
[02/10] pwm: dwc: allow driver to be built with COMPILE_TEST
commit: c901a57e39db555ad7950fd61e1470cdecc8e654
[03/10] pwm: dwc: change &pci->dev to dev in probe
commit: 8f3c7ab881ed7329003e10a2dd58f735abda2259
[04/10] pwm: dwc: move memory alloc to own function
commit: a4218d7cf8978f397e731d1f15ef33d28f77e42b
[05/10] pwm: dwc: use devm_pwmchip_add
commit: 7a77daf8223e772a225d6aa6202a5b1ae2392caf
Best regards,
--
Thierry Reding <[email protected]>
On Fri, Feb 17, 2023 at 04:08:09PM +0100, Thierry Reding wrote:
> On Fri, 23 Dec 2022 15:38:10 +0000, Ben Dooks wrote:
> > An updated set of patches for the Designware PWM driver
> > split into PCI and OF versions. I think I got all the
> > review issues in this set.
> >
> > Sorry for the delay in getting this out, between conferences
> > and other absences there has been little time to deal with
> > this set. I will be now out of office until 3rd Jan 2023.
> >
> > [...]
>
> Applied, thanks!
>
> [01/10] dt-bindings: pwm: Document Synopsys DesignWare snps,pwm-dw-apb-timers-pwm2
> commit: 0f03bf300833c05d914ab7f5ab3d8bc8564e9912
> [02/10] pwm: dwc: allow driver to be built with COMPILE_TEST
> commit: c901a57e39db555ad7950fd61e1470cdecc8e654
> [03/10] pwm: dwc: change &pci->dev to dev in probe
> commit: 8f3c7ab881ed7329003e10a2dd58f735abda2259
> [04/10] pwm: dwc: move memory alloc to own function
> commit: a4218d7cf8978f397e731d1f15ef33d28f77e42b
> [05/10] pwm: dwc: use devm_pwmchip_add
> commit: 7a77daf8223e772a225d6aa6202a5b1ae2392caf
I had some comments for patches #6 and #10. Patches #7 - #9 are still
marked as new in the PWM patchwork, but I will mark them as
changes-requested in the assumption that you'll have to rework them to
address my feedback for the other two patches anyhow.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |