USB: chipidea: i.MX: simplify usbmisc

The chipidea i.MX driver is split into two drivers. The ci_hdrc_imx driver
handles the chipidea cores and the usbmisc_imx driver handles the noncore
registers common to all chipidea cores (but SoC specific). Current flow is:

- usbmisc sets an ops pointer in the ci_hdrc_imx driver during probe
- ci_hdrc_imx checks if the pointer is valid during probe, if yes calls
  the functions in the ops pointer.
- usbmisc_imx calls back into the ci_hdrc_imx driver to get additional
  data

This is overly complicated and has problems if the drivers are compiled
as modules. In this case the usbmisc_imx driver can be unloaded even if
the ci_hdrc_imx driver still needs usbmisc functionality.

This patch changes this by letting the ci_hdrc_imx driver calling functions
from the usbmisc_imx driver. This way the symbol resolving during module
load makes sure the ci_hdrc_imx driver depends on the usbmisc_imx driver.

Also instead of letting the usbmisc_imx driver call back into the ci_hdrc_imx
driver, pass the needed data in the first place.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 76 insertions, 107 deletions

diff --git a/drivers/usb/chipidea/ci_hdrc_imx.c b/drivers/usb/chipidea/ci_hdrc_imx.c
index cc53e63c9ce9..74d998d9b45b 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.c
+++ b/drivers/usb/chipidea/ci_hdrc_imx.c
@@ -27,57 +27,48 @@ struct ci_hdrc_imx_data {
         struct usb_phy *phy;
         struct platform_device *ci_pdev;
         struct clk *clk;
+        struct imx_usbmisc_data *usbmisc_data;
 };
 
-static const struct usbmisc_ops *usbmisc_ops;
-
 /* Common functions shared by usbmisc drivers */
 
-int usbmisc_set_ops(const struct usbmisc_ops *ops)
-{
-        if (usbmisc_ops)
-                return -EBUSY;
-
-        usbmisc_ops = ops;
-
-        return 0;
-}
-EXPORT_SYMBOL_GPL(usbmisc_set_ops);
-
-void usbmisc_unset_ops(const struct usbmisc_ops *ops)
-{
-        usbmisc_ops = NULL;
-}
-EXPORT_SYMBOL_GPL(usbmisc_unset_ops);
-
-int usbmisc_get_init_data(struct device *dev, struct usbmisc_usb_device *usbdev)
+static struct imx_usbmisc_data *usbmisc_get_init_data(struct device *dev)
 {
         struct device_node *np = dev->of_node;
         struct of_phandle_args args;
+        struct imx_usbmisc_data *data;
         int ret;
 
-        usbdev->dev = dev;
+        /*
+         * In case the fsl,usbmisc property is not present this device doesn't
+         * need usbmisc. Return NULL (which is no error here)
+         */
+        if (!of_get_property(np, "fsl,usbmisc", NULL))
+                return NULL;
+
+        data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+        if (!data)
+                return ERR_PTR(-ENOMEM);
 
         ret = of_parse_phandle_with_args(np, "fsl,usbmisc", "#index-cells",
                                         0, &args);
         if (ret) {
                 dev_err(dev, "Failed to parse property fsl,usbmisc, errno %d\n",
                         ret);
-                memset(usbdev, 0, sizeof(*usbdev));
-                return ret;
+                return ERR_PTR(ret);
         }
-        usbdev->index = args.args[0];
+
+        data->index = args.args[0];
         of_node_put(args.np);
 
         if (of_find_property(np, "disable-over-current", NULL))
-                usbdev->disable_oc = 1;
+                data->disable_oc = 1;
 
         if (of_find_property(np, "external-vbus-divider", NULL))
-                usbdev->evdo = 1;
+                data->evdo = 1;
 
-        return 0;
+        return data;
 }
-EXPORT_SYMBOL_GPL(usbmisc_get_init_data);
 
 /* End of common functions shared by usbmisc drivers*/
 
@@ -92,16 +83,16 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
         };
         int ret;
 
-        if (of_find_property(pdev->dev.of_node, "fsl,usbmisc", NULL)
-                && !usbmisc_ops)
-                return -EPROBE_DEFER;
-
         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
         if (!data) {
                 dev_err(&pdev->dev, "Failed to allocate ci_hdrc-imx data!\n");
                 return -ENOMEM;
         }
 
+        data->usbmisc_data = usbmisc_get_init_data(&pdev->dev);
+        if (IS_ERR(data->usbmisc_data))
+                return PTR_ERR(data->usbmisc_data);
+
         data->clk = devm_clk_get(&pdev->dev, NULL);
         if (IS_ERR(data->clk)) {
                 dev_err(&pdev->dev,
@@ -135,11 +126,11 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
         if (!pdev->dev.coherent_dma_mask)
                 pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 
-        if (usbmisc_ops && usbmisc_ops->init) {
-                ret = usbmisc_ops->init(&pdev->dev);
+        if (data->usbmisc_data) {
+                ret = imx_usbmisc_init(data->usbmisc_data);
                 if (ret) {
-                        dev_err(&pdev->dev,
-                                "usbmisc init failed, ret=%d\n", ret);
+                        dev_err(&pdev->dev, "usbmisc init failed, ret=%d\n",
+                                        ret);
                         goto err_clk;
                 }
         }
@@ -155,11 +146,11 @@ static int ci_hdrc_imx_probe(struct platform_device *pdev)
                 goto err_clk;
         }
 
-        if (usbmisc_ops && usbmisc_ops->post) {
-                ret = usbmisc_ops->post(&pdev->dev);
+        if (data->usbmisc_data) {
+                ret = imx_usbmisc_init_post(data->usbmisc_data);
                 if (ret) {
-                        dev_err(&pdev->dev,
-                                "usbmisc post failed, ret=%d\n", ret);
+                        dev_err(&pdev->dev, "usbmisc post failed, ret=%d\n",
+                                        ret);
                         goto disable_device;
                 }
         }
diff --git a/drivers/usb/chipidea/ci_hdrc_imx.h b/drivers/usb/chipidea/ci_hdrc_imx.h
index 550bfa457620..c7271590dd0a 100644
--- a/drivers/usb/chipidea/ci_hdrc_imx.h
+++ b/drivers/usb/chipidea/ci_hdrc_imx.h
@@ -9,23 +9,12 @@
  * http://www.gnu.org/copyleft/gpl.html
  */
 
-/* Used to set SoC specific callbacks */
-struct usbmisc_ops {
-        /* It's called once when probe a usb device */
-        int (*init)(struct device *dev);
-        /* It's called once after adding a usb device */
-        int (*post)(struct device *dev);
-};
-
-struct usbmisc_usb_device {
-        struct device *dev; /* usb controller device */
+struct imx_usbmisc_data {
         int index;
 
         unsigned int disable_oc:1; /* over current detect disabled */
         unsigned int evdo:1; /* set external vbus divider option */
 };
 
-int usbmisc_set_ops(const struct usbmisc_ops *ops);
-void usbmisc_unset_ops(const struct usbmisc_ops *ops);
-int
-usbmisc_get_init_data(struct device *dev, struct usbmisc_usb_device *usbdev);
+int imx_usbmisc_init(struct imx_usbmisc_data *);
+int imx_usbmisc_init_post(struct imx_usbmisc_data *);
diff --git a/drivers/usb/chipidea/usbmisc_imx.c b/drivers/usb/chipidea/usbmisc_imx.c
index ac5a46155200..8a1094b1182f 100644
--- a/drivers/usb/chipidea/usbmisc_imx.c
+++ b/drivers/usb/chipidea/usbmisc_imx.c
@@ -18,8 +18,6 @@
 
 #include "ci_hdrc_imx.h"
 
-#define USB_DEV_MAX 4
-
 #define MX25_USB_PHY_CTRL_OFFSET        0x08
 #define MX25_BM_EXTERNAL_VBUS_DIVIDER   BIT(23)
 
@@ -32,51 +30,34 @@
 
 #define MX6_BM_OVER_CUR_DIS             BIT(7)
 
+struct usbmisc_ops {
+        /* It's called once when probe a usb device */
+        int (*init)(struct imx_usbmisc_data *data);
+        /* It's called once after adding a usb device */
+        int (*post)(struct imx_usbmisc_data *data);
+};
+
 struct imx_usbmisc {
         void __iomem *base;
         spinlock_t lock;
         struct clk *clk;
-        struct usbmisc_usb_device usbdev[USB_DEV_MAX];
         const struct usbmisc_ops *ops;
 };
 
 static struct imx_usbmisc *usbmisc;
 
-static struct usbmisc_usb_device *get_usbdev(struct device *dev)
-{
-        int i, ret;
-
-        for (i = 0; i < USB_DEV_MAX; i++) {
-                if (usbmisc->usbdev[i].dev == dev)
-                        return &usbmisc->usbdev[i];
-                else if (!usbmisc->usbdev[i].dev)
-                        break;
-        }
-
-        if (i >= USB_DEV_MAX)
-                return ERR_PTR(-EBUSY);
-
-        ret = usbmisc_get_init_data(dev, &usbmisc->usbdev[i]);
-        if (ret)
-                return ERR_PTR(ret);
-
-        return &usbmisc->usbdev[i];
-}
-
-static int usbmisc_imx25_post(struct device *dev)
+static int usbmisc_imx25_post(struct imx_usbmisc_data *data)
 {
-        struct usbmisc_usb_device *usbdev;
         void __iomem *reg;
         unsigned long flags;
         u32 val;
 
-        usbdev = get_usbdev(dev);
-        if (IS_ERR(usbdev))
-                return PTR_ERR(usbdev);
+        if (data->index > 2)
+                return -EINVAL;
 
         reg = usbmisc->base + MX25_USB_PHY_CTRL_OFFSET;
 
-        if (usbdev->evdo) {
+        if (data->evdo) {
                 spin_lock_irqsave(&usbmisc->lock, flags);
                 val = readl(reg);
                 writel(val | MX25_BM_EXTERNAL_VBUS_DIVIDER, reg);
@@ -87,20 +68,18 @@ static int usbmisc_imx25_post(struct device *dev)
         return 0;
 }
 
-static int usbmisc_imx53_init(struct device *dev)
+static int usbmisc_imx53_init(struct imx_usbmisc_data *data)
 {
-        struct usbmisc_usb_device *usbdev;
         void __iomem *reg = NULL;
         unsigned long flags;
         u32 val = 0;
 
-        usbdev = get_usbdev(dev);
-        if (IS_ERR(usbdev))
-                return PTR_ERR(usbdev);
+        if (data->index > 3)
+                return -EINVAL;
 
-        if (usbdev->disable_oc) {
+        if (data->disable_oc) {
                 spin_lock_irqsave(&usbmisc->lock, flags);
-                switch (usbdev->index) {
+                switch (data->index) {
                 case 0:
                         reg = usbmisc->base + MX53_USB_OTG_PHY_CTRL_0_OFFSET;
                         val = readl(reg) | MX53_BM_OVER_CUR_DIS_OTG;
@@ -126,22 +105,19 @@ static int usbmisc_imx53_init(struct device *dev)
         return 0;
 }
 
-static int usbmisc_imx6q_init(struct device *dev)
+static int usbmisc_imx6q_init(struct imx_usbmisc_data *data)
 {
-
-        struct usbmisc_usb_device *usbdev;
         unsigned long flags;
         u32 reg;
 
-        usbdev = get_usbdev(dev);
-        if (IS_ERR(usbdev))
-                return PTR_ERR(usbdev);
+        if (data->index > 3)
+                return -EINVAL;
 
-        if (usbdev->disable_oc) {
+        if (data->disable_oc) {
                 spin_lock_irqsave(&usbmisc->lock, flags);
-                reg = readl(usbmisc->base + usbdev->index * 4);
+                reg = readl(usbmisc->base + data->index * 4);
                 writel(reg | MX6_BM_OVER_CUR_DIS,
-                        usbmisc->base + usbdev->index * 4);
+                        usbmisc->base + data->index * 4);
                 spin_unlock_irqrestore(&usbmisc->lock, flags);
         }
 
@@ -160,6 +136,26 @@ static const struct usbmisc_ops imx6q_usbmisc_ops = {
         .init = usbmisc_imx6q_init,
 };
 
+int imx_usbmisc_init(struct imx_usbmisc_data *data)
+{
+        if (!usbmisc)
+                return -EPROBE_DEFER;
+        if (!usbmisc->ops->init)
+                return 0;
+        return usbmisc->ops->init(data);
+}
+EXPORT_SYMBOL_GPL(imx_usbmisc_init);
+
+int imx_usbmisc_init_post(struct imx_usbmisc_data *data)
+{
+        if (!usbmisc)
+                return -EPROBE_DEFER;
+        if (!usbmisc->ops->post)
+                return 0;
+        return usbmisc->ops->post(data);
+}
+EXPORT_SYMBOL_GPL(imx_usbmisc_init_post);
+
 static const struct of_device_id usbmisc_imx_dt_ids[] = {
         {
                 .compatible = "fsl,imx25-usbmisc",
@@ -216,19 +212,12 @@ static int usbmisc_imx_probe(struct platform_device *pdev)
                 of_match_device(usbmisc_imx_dt_ids, &pdev->dev);
         data->ops = (const struct usbmisc_ops *)tmp_dev->data;
         usbmisc = data;
-        ret = usbmisc_set_ops(data->ops);
-        if (ret) {
-                usbmisc = NULL;
-                clk_disable_unprepare(data->clk);
-                return ret;
-        }
 
         return 0;
 }
 
 static int usbmisc_imx_remove(struct platform_device *pdev)
 {
-        usbmisc_unset_ops(usbmisc->ops);
         clk_disable_unprepare(usbmisc->clk);
         usbmisc = NULL;
         return 0;