[RFC v4 06/10] pwm: dwc: split pci out of core driver

From: Ben Dooks
Date: Tue Aug 16 2022 - 17:15:40 EST


Moving towards adding non-pci support for the driver, move the pci
parts out of the core into their own module. This is partly due to
the module_driver() code only being allowed once in a module and also
to avoid a number of #ifdef if we build a single file in a system
without pci support.

Signed-off-by: Ben Dooks <ben.dooks@xxxxxxxxxx>
---
drivers/pwm/Kconfig | 14 +++-
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-dwc-pci.c | 133 ++++++++++++++++++++++++++++++++
drivers/pwm/pwm-dwc.c | 158 +-------------------------------------
drivers/pwm/pwm-dwc.h | 58 ++++++++++++++
5 files changed, 207 insertions(+), 157 deletions(-)
create mode 100644 drivers/pwm/pwm-dwc-pci.c
create mode 100644 drivers/pwm/pwm-dwc.h

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 3f3c53af4a56..a9f1c554db2b 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -175,15 +175,23 @@ config PWM_CROS_EC
Controller.

config PWM_DWC
- tristate "DesignWare PWM Controller"
- depends on PCI || COMPILE_TEST
+ tristate "DesignWare PWM Controller core"
depends on HAS_IOMEM
help
- PWM driver for Synopsys DWC PWM Controller attached to a PCI bus.
+ PWM driver for Synopsys DWC PWM Controller.

To compile this driver as a module, choose M here: the module
will be called pwm-dwc.

+config PWM_DWC_PCI
+ tristate "DesignWare PWM Controller core"
+ depends on PWM_DWC && HAS_IOMEM && PCI
+ help
+ PWM driver for Synopsys DWC PWM Controller attached to a PCI bus.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-dwc-pci.
+
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 7bf1a29f02b8..a70d36623129 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-$(CONFIG_PWM_DWC_PCI) += pwm-dwc-pci.o
obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o
obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o
obj-$(CONFIG_PWM_HIBVT) += pwm-hibvt.o
diff --git a/drivers/pwm/pwm-dwc-pci.c b/drivers/pwm/pwm-dwc-pci.c
new file mode 100644
index 000000000000..2213d0e7f3c8
--- /dev/null
+++ b/drivers/pwm/pwm-dwc-pci.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DesignWare PWM Controller driver (PCI part)
+ *
+ * Copyright (C) 2018-2020 Intel Corporation
+ *
+ * Author: Felipe Balbi (Intel)
+ * Author: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
+ * Author: Raymond Tan <raymond.tan@xxxxxxxxx>
+ *
+ * Limitations:
+ * - The hardware cannot generate a 0 % or 100 % duty cycle. Both high and low
+ * periods are one or more input clock periods long.
+ */
+
+#include <linux/bitops.h>
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+
+#include "pwm-dwc.h"
+
+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 = 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));
+ return ret;
+ }
+
+ pci_set_master(pci);
+
+ ret = pcim_iomap_regions(pci, BIT(0), pci_name(pci));
+ if (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(dev, "Base address missing\n");
+ return -ENOMEM;
+ }
+
+ ret = devm_pwmchip_add(dev, &dwc->chip);
+ if (ret)
+ return ret;
+
+ pm_runtime_put(dev);
+ pm_runtime_allow(dev);
+
+ return 0;
+}
+
+static void dwc_pwm_remove(struct pci_dev *pci)
+{
+ pm_runtime_forbid(&pci->dev);
+ pm_runtime_get_noresume(&pci->dev);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dwc_pwm_suspend(struct device *dev)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct dwc_pwm *dwc = pci_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < DWC_TIMERS_TOTAL; i++) {
+ if (dwc->chip.pwms[i].state.enabled) {
+ dev_err(dev, "PWM %u in use by consumer (%s)\n",
+ i, dwc->chip.pwms[i].label);
+ return -EBUSY;
+ }
+ dwc->ctx[i].cnt = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(i));
+ dwc->ctx[i].cnt2 = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(i));
+ dwc->ctx[i].ctrl = dwc_pwm_readl(dwc, DWC_TIM_CTRL(i));
+ }
+
+ return 0;
+}
+
+static int dwc_pwm_resume(struct device *dev)
+{
+ struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
+ struct dwc_pwm *dwc = pci_get_drvdata(pdev);
+ int i;
+
+ for (i = 0; i < DWC_TIMERS_TOTAL; i++) {
+ dwc_pwm_writel(dwc, dwc->ctx[i].cnt, DWC_TIM_LD_CNT(i));
+ dwc_pwm_writel(dwc, dwc->ctx[i].cnt2, DWC_TIM_LD_CNT2(i));
+ dwc_pwm_writel(dwc, dwc->ctx[i].ctrl, DWC_TIM_CTRL(i));
+ }
+
+ return 0;
+}
+#endif
+
+static 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 */
+ { } /* Terminating Entry */
+};
+MODULE_DEVICE_TABLE(pci, dwc_pwm_id_table);
+
+static struct pci_driver dwc_pwm_driver = {
+ .name = "pwm-dwc",
+ .probe = dwc_pwm_probe,
+ .remove = dwc_pwm_remove,
+ .id_table = dwc_pwm_id_table,
+ .driver = {
+ .pm = &dwc_pwm_pm_ops,
+ },
+};
+
+module_pci_driver(dwc_pwm_driver);
+
+MODULE_AUTHOR("Felipe Balbi (Intel)");
+MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>");
+MODULE_AUTHOR("Raymond Tan <raymond.tan@xxxxxxxxx>");
+MODULE_DESCRIPTION("DesignWare PWM Controller");
+MODULE_LICENSE("GPL");
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index 56cde9da2c0e..90a8ae1252a1 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -1,16 +1,12 @@
// SPDX-License-Identifier: GPL-2.0
/*
- * DesignWare PWM Controller driver
+ * DesignWare PWM Controller driver core
*
* Copyright (C) 2018-2020 Intel Corporation
*
* Author: Felipe Balbi (Intel)
* Author: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
* Author: Raymond Tan <raymond.tan@xxxxxxxxx>
- *
- * Limitations:
- * - The hardware cannot generate a 0 % or 100 % duty cycle. Both high and low
- * periods are one or more input clock periods long.
*/

#include <linux/bitops.h>
@@ -21,51 +17,7 @@
#include <linux/pm_runtime.h>
#include <linux/pwm.h>

-#define DWC_TIM_LD_CNT(n) ((n) * 0x14)
-#define DWC_TIM_LD_CNT2(n) (((n) * 4) + 0xb0)
-#define DWC_TIM_CUR_VAL(n) (((n) * 0x14) + 0x04)
-#define DWC_TIM_CTRL(n) (((n) * 0x14) + 0x08)
-#define DWC_TIM_EOI(n) (((n) * 0x14) + 0x0c)
-#define DWC_TIM_INT_STS(n) (((n) * 0x14) + 0x10)
-
-#define DWC_TIMERS_INT_STS 0xa0
-#define DWC_TIMERS_EOI 0xa4
-#define DWC_TIMERS_RAW_INT_STS 0xa8
-#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)
-#define DWC_TIM_CTRL_MODE BIT(1)
-#define DWC_TIM_CTRL_MODE_FREE (0 << 1)
-#define DWC_TIM_CTRL_MODE_USER (1 << 1)
-#define DWC_TIM_CTRL_INT_MASK BIT(2)
-#define DWC_TIM_CTRL_PWM BIT(3)
-
-struct dwc_pwm_ctx {
- u32 cnt;
- u32 cnt2;
- u32 ctrl;
-};
-
-struct dwc_pwm {
- struct pwm_chip chip;
- void __iomem *base;
- struct dwc_pwm_ctx ctx[DWC_TIMERS_TOTAL];
-};
-#define to_dwc_pwm(p) (container_of((p), struct dwc_pwm, chip))
-
-static inline u32 dwc_pwm_readl(struct dwc_pwm *dwc, u32 offset)
-{
- return readl(dwc->base + offset);
-}
-
-static inline void dwc_pwm_writel(struct dwc_pwm *dwc, u32 value, u32 offset)
-{
- writel(value, dwc->base + offset);
-}
+#include "pwm-dwc.h"

static void __dwc_pwm_set_enable(struct dwc_pwm *dwc, int pwm, int enabled)
{
@@ -196,7 +148,7 @@ 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_pwm_alloc(struct device *dev)
{
struct dwc_pwm *dwc;

@@ -211,109 +163,7 @@ static struct dwc_pwm *dwc_pwm_alloc(struct device *dev)
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 = 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));
- return ret;
- }
-
- pci_set_master(pci);
-
- ret = pcim_iomap_regions(pci, BIT(0), pci_name(pci));
- if (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(dev, "Base address missing\n");
- return -ENOMEM;
- }
-
- ret = devm_pwmchip_add(dev, &dwc->chip);
- if (ret)
- return ret;
-
- pm_runtime_put(dev);
- pm_runtime_allow(dev);
-
- return 0;
-}
-
-static void dwc_pwm_remove(struct pci_dev *pci)
-{
- pm_runtime_forbid(&pci->dev);
- pm_runtime_get_noresume(&pci->dev);
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int dwc_pwm_suspend(struct device *dev)
-{
- struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
- struct dwc_pwm *dwc = pci_get_drvdata(pdev);
- int i;
-
- for (i = 0; i < DWC_TIMERS_TOTAL; i++) {
- if (dwc->chip.pwms[i].state.enabled) {
- dev_err(dev, "PWM %u in use by consumer (%s)\n",
- i, dwc->chip.pwms[i].label);
- return -EBUSY;
- }
- dwc->ctx[i].cnt = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT(i));
- dwc->ctx[i].cnt2 = dwc_pwm_readl(dwc, DWC_TIM_LD_CNT2(i));
- dwc->ctx[i].ctrl = dwc_pwm_readl(dwc, DWC_TIM_CTRL(i));
- }
-
- return 0;
-}
-
-static int dwc_pwm_resume(struct device *dev)
-{
- struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
- struct dwc_pwm *dwc = pci_get_drvdata(pdev);
- int i;
-
- for (i = 0; i < DWC_TIMERS_TOTAL; i++) {
- dwc_pwm_writel(dwc, dwc->ctx[i].cnt, DWC_TIM_LD_CNT(i));
- dwc_pwm_writel(dwc, dwc->ctx[i].cnt2, DWC_TIM_LD_CNT2(i));
- dwc_pwm_writel(dwc, dwc->ctx[i].ctrl, DWC_TIM_CTRL(i));
- }
-
- return 0;
-}
-#endif
-
-static 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 */
- { } /* Terminating Entry */
-};
-MODULE_DEVICE_TABLE(pci, dwc_pwm_id_table);
-
-static struct pci_driver dwc_pwm_driver = {
- .name = "pwm-dwc",
- .probe = dwc_pwm_probe,
- .remove = dwc_pwm_remove,
- .id_table = dwc_pwm_id_table,
- .driver = {
- .pm = &dwc_pwm_pm_ops,
- },
-};
-
-module_pci_driver(dwc_pwm_driver);
+EXPORT_SYMBOL_GPL(dwc_pwm_alloc);

MODULE_AUTHOR("Felipe Balbi (Intel)");
MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>");
diff --git a/drivers/pwm/pwm-dwc.h b/drivers/pwm/pwm-dwc.h
new file mode 100644
index 000000000000..68f98eb76152
--- /dev/null
+++ b/drivers/pwm/pwm-dwc.h
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * DesignWare PWM Controller driver
+ *
+ * Copyright (C) 2018-2020 Intel Corporation
+ *
+ * Author: Felipe Balbi (Intel)
+ * Author: Jarkko Nikula <jarkko.nikula@xxxxxxxxxxxxxxx>
+ * Author: Raymond Tan <raymond.tan@xxxxxxxxx>
+ */
+
+#define DWC_TIM_LD_CNT(n) ((n) * 0x14)
+#define DWC_TIM_LD_CNT2(n) (((n) * 4) + 0xb0)
+#define DWC_TIM_CUR_VAL(n) (((n) * 0x14) + 0x04)
+#define DWC_TIM_CTRL(n) (((n) * 0x14) + 0x08)
+#define DWC_TIM_EOI(n) (((n) * 0x14) + 0x0c)
+#define DWC_TIM_INT_STS(n) (((n) * 0x14) + 0x10)
+
+#define DWC_TIMERS_INT_STS 0xa0
+#define DWC_TIMERS_EOI 0xa4
+#define DWC_TIMERS_RAW_INT_STS 0xa8
+#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)
+#define DWC_TIM_CTRL_MODE BIT(1)
+#define DWC_TIM_CTRL_MODE_FREE (0 << 1)
+#define DWC_TIM_CTRL_MODE_USER (1 << 1)
+#define DWC_TIM_CTRL_INT_MASK BIT(2)
+#define DWC_TIM_CTRL_PWM BIT(3)
+
+struct dwc_pwm_ctx {
+ u32 cnt;
+ u32 cnt2;
+ u32 ctrl;
+};
+
+struct dwc_pwm {
+ struct pwm_chip chip;
+ void __iomem *base;
+ struct dwc_pwm_ctx ctx[DWC_TIMERS_TOTAL];
+};
+#define to_dwc_pwm(p) (container_of((p), struct dwc_pwm, chip))
+
+static inline u32 dwc_pwm_readl(struct dwc_pwm *dwc, u32 offset)
+{
+ return readl(dwc->base + offset);
+}
+
+static inline void dwc_pwm_writel(struct dwc_pwm *dwc, u32 value, u32 offset)
+{
+ writel(value, dwc->base + offset);
+}
+
+extern struct dwc_pwm *dwc_pwm_alloc(struct device *dev);
--
2.35.1