pwm: lpss: Add support for PCI devices

Not all systems enumerate the PWM devices via ACPI. They can also be
exposed via the PCI interface.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Chew, Chiau Ee <chiau.ee.chew@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

1 files changed, 130 insertions, 31 deletions

diff --git a/drivers/pwm/pwm-lpss.c b/drivers/pwm/pwm-lpss.c
index 449e372050a0..c718ad1df3bb 100644
--- a/drivers/pwm/pwm-lpss.c
+++ b/drivers/pwm/pwm-lpss.c
@@ -6,6 +6,7 @@
  * Author: Chew Kean Ho <kean.ho.chew@intel.com>
  * Author: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com>
  * Author: Chew Chiau Ee <chiau.ee.chew@intel.com>
+ * Author: Alan Cox <alan@linux.intel.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -19,6 +20,9 @@
 #include <linux/module.h>
 #include <linux/pwm.h>
 #include <linux/platform_device.h>
+#include <linux/pci.h>
+
+static int pci_drv, plat_drv;   /* So we know which drivers registered */
 
 #define PWM                             0x00000000
 #define PWM_ENABLE                      BIT(31)
@@ -34,6 +38,16 @@ struct pwm_lpss_chip {
         struct pwm_chip chip;
         void __iomem *regs;
         struct clk *clk;
+        unsigned long clk_rate;
+};
+
+struct pwm_lpss_boardinfo {
+        unsigned long clk_rate;
+};
+
+/* BayTrail */
+static const struct pwm_lpss_boardinfo byt_info = {
+        25000000
 };
 
 static inline struct pwm_lpss_chip *to_lpwm(struct pwm_chip *chip)
@@ -55,7 +69,7 @@ static int pwm_lpss_config(struct pwm_chip *chip, struct pwm_device *pwm,
         /* The equation is: base_unit = ((freq / c) * 65536) + correction */
         base_unit = freq * 65536;
 
-        c = clk_get_rate(lpwm->clk);
+        c = lpwm->clk_rate;
         if (!c)
                 return -EINVAL;
 
@@ -113,52 +127,48 @@ static const struct pwm_ops pwm_lpss_ops = {
         .owner = THIS_MODULE,
 };
 
-static const struct acpi_device_id pwm_lpss_acpi_match[] = {
-        { "80860F09", 0 },
-        { },
-};
-MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
-
-static int pwm_lpss_probe(struct platform_device *pdev)
+static struct pwm_lpss_chip *pwm_lpss_probe(struct device *dev,
+                                            struct resource *r,
+                                            struct pwm_lpss_boardinfo *info)
 {
         struct pwm_lpss_chip *lpwm;
-        struct resource *r;
         int ret;
 
-        lpwm = devm_kzalloc(&pdev->dev, sizeof(*lpwm), GFP_KERNEL);
+        lpwm = devm_kzalloc(dev, sizeof(*lpwm), GFP_KERNEL);
         if (!lpwm)
-                return -ENOMEM;
-
-        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+                return ERR_PTR(-ENOMEM);
 
-        lpwm->regs = devm_ioremap_resource(&pdev->dev, r);
+        lpwm->regs = devm_ioremap_resource(dev, r);
         if (IS_ERR(lpwm->regs))
-                return PTR_ERR(lpwm->regs);
-
-        lpwm->clk = devm_clk_get(&pdev->dev, NULL);
-        if (IS_ERR(lpwm->clk)) {
-                dev_err(&pdev->dev, "failed to get PWM clock\n");
-                return PTR_ERR(lpwm->clk);
+                return lpwm->regs;
+
+        if (info) {
+                lpwm->clk_rate = info->clk_rate;
+        } else {
+                lpwm->clk = devm_clk_get(dev, NULL);
+                if (IS_ERR(lpwm->clk)) {
+                        dev_err(dev, "failed to get PWM clock\n");
+                        return ERR_CAST(lpwm->clk);
+                }
+                lpwm->clk_rate = clk_get_rate(lpwm->clk);
         }
 
-        lpwm->chip.dev = &pdev->dev;
+        lpwm->chip.dev = dev;
         lpwm->chip.ops = &pwm_lpss_ops;
         lpwm->chip.base = -1;
         lpwm->chip.npwm = 1;
 
         ret = pwmchip_add(&lpwm->chip);
         if (ret) {
-                dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
-                return ret;
+                dev_err(dev, "failed to add PWM chip: %d\n", ret);
+                return ERR_PTR(ret);
         }
 
-        platform_set_drvdata(pdev, lpwm);
-        return 0;
+        return lpwm;
 }
 
-static int pwm_lpss_remove(struct platform_device *pdev)
+static int pwm_lpss_remove(struct pwm_lpss_chip *lpwm)
 {
-        struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev);
         u32 ctrl;
 
         ctrl = readl(lpwm->regs + PWM);
@@ -167,15 +177,104 @@ static int pwm_lpss_remove(struct platform_device *pdev)
         return pwmchip_remove(&lpwm->chip);
 }
 
-static struct platform_driver pwm_lpss_driver = {
+static int pwm_lpss_probe_pci(struct pci_dev *pdev,
+                              const struct pci_device_id *id)
+{
+        const struct pwm_lpss_boardinfo *info;
+        struct pwm_lpss_chip *lpwm;
+        int err;
+
+        err = pci_enable_device(pdev);
+        if (err < 0)
+                return err;
+
+        info = (struct pwm_lpss_boardinfo *)id->driver_data;
+        lpwm = pwm_lpss_probe(&pdev->dev, &pdev->resource[0], info);
+        if (IS_ERR(lpwm))
+                return PTR_ERR(lpwm);
+
+        pci_set_drvdata(pdev, lpwm);
+        return 0;
+}
+
+static void pwm_lpss_remove_pci(struct pci_dev *pdev)
+{
+        struct pwm_lpss_chip *lpwm = pci_get_drvdata(pdev);
+
+        pwm_lpss_remove(lpwm);
+        pci_disable_device(pdev);
+}
+
+static struct pci_device_id pwm_lpss_pci_ids[] = {
+        { PCI_VDEVICE(INTEL, 0x0f08), (unsigned long)&byt_info},
+        { PCI_VDEVICE(INTEL, 0x0f09), (unsigned long)&byt_info},
+        { },
+};
+MODULE_DEVICE_TABLE(pci, pwm_lpss_pci_ids);
+
+static struct pci_driver pwm_lpss_driver_pci = {
+        .name = "pwm-lpss",
+        .id_table = pwm_lpss_pci_ids,
+        .probe = pwm_lpss_probe_pci,
+        .remove = pwm_lpss_remove_pci,
+};
+
+static int pwm_lpss_probe_platform(struct platform_device *pdev)
+{
+        struct pwm_lpss_chip *lpwm;
+        struct resource *r;
+
+        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+        lpwm = pwm_lpss_probe(&pdev->dev, r, NULL);
+        if (IS_ERR(lpwm))
+                return PTR_ERR(lpwm);
+
+        platform_set_drvdata(pdev, lpwm);
+        return 0;
+}
+
+static int pwm_lpss_remove_platform(struct platform_device *pdev)
+{
+        struct pwm_lpss_chip *lpwm = platform_get_drvdata(pdev);
+
+        return pwm_lpss_remove(lpwm);
+}
+
+static const struct acpi_device_id pwm_lpss_acpi_match[] = {
+        { "80860F09", 0 },
+        { },
+};
+MODULE_DEVICE_TABLE(acpi, pwm_lpss_acpi_match);
+
+static struct platform_driver pwm_lpss_driver_platform = {
         .driver = {
                 .name = "pwm-lpss",
                 .acpi_match_table = pwm_lpss_acpi_match,
         },
-        .probe = pwm_lpss_probe,
-        .remove = pwm_lpss_remove,
+        .probe = pwm_lpss_probe_platform,
+        .remove = pwm_lpss_remove_platform,
 };
-module_platform_driver(pwm_lpss_driver);
+
+static int __init pwm_init(void)
+{
+        pci_drv = pci_register_driver(&pwm_lpss_driver_pci);
+        plat_drv = platform_driver_register(&pwm_lpss_driver_platform);
+        if (pci_drv && plat_drv)
+                return pci_drv;
+
+        return 0;
+}
+module_init(pwm_init);
+
+static void __exit pwm_exit(void)
+{
+        if (!pci_drv)
+                pci_unregister_driver(&pwm_lpss_driver_pci);
+        if (!plat_drv)
+                platform_driver_unregister(&pwm_lpss_driver_platform);
+}
+module_exit(pwm_exit);
 
 MODULE_DESCRIPTION("PWM driver for Intel LPSS");
 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");