[PATCH v1 1/3] pwm: dwc: Add 16 channel support for Intel Elkhart Lake

From: Raag Jadav
Date: Sun Jan 21 2024 - 22:03:04 EST


Intel Elkhart Lake PSE includes two instances of PWM as a single PCI
function with 8 channels each. Add support for the remaining channels.

Signed-off-by: Raag Jadav <raag.jadav@xxxxxxxxx>
Tested-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@xxxxxxxxx>
---
drivers/pwm/pwm-dwc.c | 51 +++++++++++++++++++++++++++++++++++--------
drivers/pwm/pwm-dwc.h | 5 +++++
2 files changed, 47 insertions(+), 9 deletions(-)

diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index 4929354f8cd9..fd64313cb38d 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -25,16 +25,48 @@

#include "pwm-dwc.h"

+/* Elkhart Lake */
+static const struct dwc_pwm_info ehl_pwm_info = {
+ .nr = 2,
+ .size = 0x1000,
+};
+
+static int dwc_pwm_init(struct device *dev, const struct dwc_pwm_info *info, void __iomem *base)
+{
+ /* Default values for single instance devices */
+ unsigned int nr = 1, size = 0;
+ int i, ret;
+
+ /* Fill up values from driver_data, if any */
+ if (info) {
+ nr = info->nr;
+ size = info->size;
+ }
+
+ for (i = 0; i < nr; i++) {
+ struct dwc_pwm *dwc;
+
+ dwc = dwc_pwm_alloc(dev);
+ if (!dwc)
+ return -ENOMEM;
+
+ dwc->base = base + (i * size);
+
+ ret = devm_pwmchip_add(dev, &dwc->chip);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
{
+ const struct dwc_pwm_info *info;
struct device *dev = &pci->dev;
- struct dwc_pwm *dwc;
+ void __iomem *base;
int ret;

- dwc = dwc_pwm_alloc(dev);
- if (!dwc)
- return -ENOMEM;
-
ret = pcim_enable_device(pci);
if (ret) {
dev_err(dev, "Failed to enable device (%pe)\n", ERR_PTR(ret));
@@ -49,13 +81,14 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
return ret;
}

- dwc->base = pcim_iomap_table(pci)[0];
- if (!dwc->base) {
+ base = pcim_iomap_table(pci)[0];
+ if (!base) {
dev_err(dev, "Base address missing\n");
return -ENOMEM;
}

- ret = devm_pwmchip_add(dev, &dwc->chip);
+ info = (const struct dwc_pwm_info *)id->driver_data;
+ ret = dwc_pwm_init(dev, info, base);
if (ret)
return ret;

@@ -109,7 +142,7 @@ static int dwc_pwm_resume(struct device *dev)
static DEFINE_SIMPLE_DEV_PM_OPS(dwc_pwm_pm_ops, dwc_pwm_suspend, dwc_pwm_resume);

static const struct pci_device_id dwc_pwm_id_table[] = {
- { PCI_VDEVICE(INTEL, 0x4bb7) }, /* Elkhart Lake */
+ { PCI_VDEVICE(INTEL, 0x4bb7), (kernel_ulong_t)&ehl_pwm_info },
{ } /* Terminating Entry */
};
MODULE_DEVICE_TABLE(pci, dwc_pwm_id_table);
diff --git a/drivers/pwm/pwm-dwc.h b/drivers/pwm/pwm-dwc.h
index 64795247c54c..c9bbfc77b568 100644
--- a/drivers/pwm/pwm-dwc.h
+++ b/drivers/pwm/pwm-dwc.h
@@ -33,6 +33,11 @@ MODULE_IMPORT_NS(dwc_pwm);
#define DWC_TIM_CTRL_INT_MASK BIT(2)
#define DWC_TIM_CTRL_PWM BIT(3)

+struct dwc_pwm_info {
+ unsigned int nr;
+ unsigned int size;
+};
+
struct dwc_pwm_ctx {
u32 cnt;
u32 cnt2;
--
2.35.3