i2c-nomadik: turn the platform driver to an amba driver

The i2c-nomadik gateware is really a PrimeCell APB device. By hosting
the driver under the amba bus we can access it more easily, for
example using the generic pci-amba driver. The patch also fixes the
mach-ux500 users, so they register an amba device instead than a
platform device.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

2 files changed, 78 insertions, 86 deletions

diff --git a/arch/arm/mach-ux500/devices-common.h b/arch/arm/mach-ux500/devices-common.h
index 23cf734b5384..ecdd8386cffb 100644
--- a/arch/arm/mach-ux500/devices-common.h
+++ b/arch/arm/mach-ux500/devices-common.h
@@ -56,27 +56,15 @@ dbx500_add_uart(struct device *parent, const char *name, resource_size_t base,
 
 struct nmk_i2c_controller;
 
-static inline struct platform_device *
+static inline struct amba_device *
 dbx500_add_i2c(struct device *parent, int id, resource_size_t base, int irq,
                struct nmk_i2c_controller *data)
 {
-        struct resource res[] = {
-                DEFINE_RES_MEM(base, SZ_4K),
-                DEFINE_RES_IRQ(irq),
-        };
+        /* Conjure a name similar to what the platform device used to have */
+        char name[16];
 
-        struct platform_device_info pdevinfo = {
-                .parent = parent,
-                .name = "nmk-i2c",
-                .id = id,
-                .res = res,
-                .num_res = ARRAY_SIZE(res),
-                .data = data,
-                .size_data = sizeof(*data),
-                .dma_mask = DMA_BIT_MASK(32),
-        };
-
-        return platform_device_register_full(&pdevinfo);
+        snprintf(name, sizeof(name), "nmk-i2c.%d", id);
+        return amba_apb_device_add(parent, name, base, SZ_4K, irq, 0, data, 0);
 }
 
 static inline struct amba_device *
diff --git a/drivers/i2c/busses/i2c-nomadik.c b/drivers/i2c/busses/i2c-nomadik.c
index 752f1fda371f..6db453fe68e6 100644
--- a/drivers/i2c/busses/i2c-nomadik.c
+++ b/drivers/i2c/busses/i2c-nomadik.c
@@ -14,7 +14,8 @@
  */
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/platform_device.h>
+#include <linux/amba/bus.h>
+#include <linux/atomic.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/i2c.h>
@@ -135,7 +136,7 @@ struct i2c_nmk_client {
 
 /**
  * struct nmk_i2c_dev - private data structure of the controller.
- * @pdev: parent platform device.
+ * @adev: parent amba device.
  * @adap: corresponding I2C adapter.
  * @irq: interrupt line for the controller.
  * @virtbase: virtual io memory area.
@@ -149,7 +150,7 @@ struct i2c_nmk_client {
  * @busy: Busy doing transfer.
  */
 struct nmk_i2c_dev {
-        struct platform_device          *pdev;
+        struct amba_device              *adev;
         struct i2c_adapter              adap;
         int                             irq;
         void __iomem                    *virtbase;
@@ -216,7 +217,7 @@ static int flush_i2c_fifo(struct nmk_i2c_dev *dev)
                 }
         }
 
-        dev_err(&dev->pdev->dev,
+        dev_err(&dev->adev->dev,
                 "flushing operation timed out giving up after %d attempts",
                 LOOP_ATTEMPTS);
 
@@ -363,7 +364,7 @@ static void setup_i2c_controller(struct nmk_i2c_dev *dev)
          * and high speed (up to 3.4 Mb/s)
          */
         if (dev->cfg.sm > I2C_FREQ_MODE_FAST) {
-                dev_err(&dev->pdev->dev,
+                dev_err(&dev->adev->dev,
                         "do not support this mode defaulting to std. mode\n");
                 brcr2 = i2c_clk/(100000 * 2) & 0xffff;
                 writel((brcr1 | brcr2), dev->virtbase + I2C_BRCR);
@@ -422,7 +423,7 @@ static int read_i2c(struct nmk_i2c_dev *dev)
                 &dev->xfer_complete, dev->adap.timeout);
 
         if (timeout < 0) {
-                dev_err(&dev->pdev->dev,
+                dev_err(&dev->adev->dev,
                         "wait_for_completion_timeout "
                         "returned %d waiting for event\n", timeout);
                 status = timeout;
@@ -430,7 +431,7 @@ static int read_i2c(struct nmk_i2c_dev *dev)
 
         if (timeout == 0) {
                 /* Controller timed out */
-                dev_err(&dev->pdev->dev, "read from slave 0x%x timed out\n",
+                dev_err(&dev->adev->dev, "read from slave 0x%x timed out\n",
                                 dev->cli.slave_adr);
                 status = -ETIMEDOUT;
         }
@@ -509,7 +510,7 @@ static int write_i2c(struct nmk_i2c_dev *dev)
                 &dev->xfer_complete, dev->adap.timeout);
 
         if (timeout < 0) {
-                dev_err(&dev->pdev->dev,
+                dev_err(&dev->adev->dev,
                         "wait_for_completion_timeout "
                         "returned %d waiting for event\n", timeout);
                 status = timeout;
@@ -517,7 +518,7 @@ static int write_i2c(struct nmk_i2c_dev *dev)
 
         if (timeout == 0) {
                 /* Controller timed out */
-                dev_err(&dev->pdev->dev, "write to slave 0x%x timed out\n",
+                dev_err(&dev->adev->dev, "write to slave 0x%x timed out\n",
                                 dev->cli.slave_adr);
                 status = -ETIMEDOUT;
         }
@@ -556,7 +557,7 @@ static int nmk_i2c_xfer_one(struct nmk_i2c_dev *dev, u16 flags)
                 if (((i2c_sr >> 2) & 0x3) == 0x3) {
                         /* get the abort cause */
                         cause = (i2c_sr >> 4) & 0x7;
-                        dev_err(&dev->pdev->dev, "%s\n",
+                        dev_err(&dev->adev->dev, "%s\n",
                                 cause >= ARRAY_SIZE(abort_causes) ?
                                 "unknown reason" :
                                 abort_causes[cause]);
@@ -629,7 +630,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
 
         if (dev->regulator)
                 regulator_enable(dev->regulator);
-        pm_runtime_get_sync(&dev->pdev->dev);
+        pm_runtime_get_sync(&dev->adev->dev);
 
         clk_enable(dev->clk);
 
@@ -644,7 +645,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
 
                 for (i = 0; i < num_msgs; i++) {
                         if (unlikely(msgs[i].flags & I2C_M_TEN)) {
-                                dev_err(&dev->pdev->dev,
+                                dev_err(&dev->adev->dev,
                                         "10 bit addressing not supported\n");
 
                                 status = -EINVAL;
@@ -666,7 +667,7 @@ static int nmk_i2c_xfer(struct i2c_adapter *i2c_adap,
 
 out:
         clk_disable(dev->clk);
-        pm_runtime_put_sync(&dev->pdev->dev);
+        pm_runtime_put_sync(&dev->adev->dev);
         if (dev->regulator)
                 regulator_disable(dev->regulator);
 
@@ -789,7 +790,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg)
 
                 if (dev->cli.count) {
                         dev->result = -EIO;
-                        dev_err(&dev->pdev->dev,
+                        dev_err(&dev->adev->dev,
                                 "%lu bytes still remain to be xfered\n",
                                 dev->cli.count);
                         (void) init_hw(dev);
@@ -833,7 +834,7 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg)
                 dev->result = -EIO;
                 (void) init_hw(dev);
 
-                dev_err(&dev->pdev->dev, "Tx Fifo Over run\n");
+                dev_err(&dev->adev->dev, "Tx Fifo Over run\n");
                 complete(&dev->xfer_complete);
 
                 break;
@@ -846,10 +847,10 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg)
         case I2C_IT_RFSE:
         case I2C_IT_WTSR:
         case I2C_IT_STD:
-                dev_err(&dev->pdev->dev, "unhandled Interrupt\n");
+                dev_err(&dev->adev->dev, "unhandled Interrupt\n");
                 break;
         default:
-                dev_err(&dev->pdev->dev, "spurious Interrupt..\n");
+                dev_err(&dev->adev->dev, "spurious Interrupt..\n");
                 break;
         }
 
@@ -860,8 +861,8 @@ static irqreturn_t i2c_irq_handler(int irq, void *arg)
 #ifdef CONFIG_PM
 static int nmk_i2c_suspend(struct device *dev)
 {
-        struct platform_device *pdev = to_platform_device(dev);
-        struct nmk_i2c_dev *nmk_i2c = platform_get_drvdata(pdev);
+        struct amba_device *adev = to_amba_device(dev);
+        struct nmk_i2c_dev *nmk_i2c = amba_get_drvdata(adev);
 
         if (nmk_i2c->busy)
                 return -EBUSY;
@@ -898,79 +899,70 @@ static const struct i2c_algorithm nmk_i2c_algo = {
         .functionality  = nmk_i2c_functionality
 };
 
-static int __devinit nmk_i2c_probe(struct platform_device *pdev)
+static atomic_t adapter_id = ATOMIC_INIT(0);
+
+static int nmk_i2c_probe(struct amba_device *adev, const struct amba_id *id)
 {
         int ret = 0;
-        struct resource *res;
         struct nmk_i2c_controller *pdata =
-                        pdev->dev.platform_data;
+                        adev->dev.platform_data;
         struct nmk_i2c_dev      *dev;
         struct i2c_adapter *adap;
 
+        if (!pdata) {
+                dev_warn(&adev->dev, "no platform data\n");
+                return -ENODEV;
+        }
         dev = kzalloc(sizeof(struct nmk_i2c_dev), GFP_KERNEL);
         if (!dev) {
-                dev_err(&pdev->dev, "cannot allocate memory\n");
+                dev_err(&adev->dev, "cannot allocate memory\n");
                 ret = -ENOMEM;
                 goto err_no_mem;
         }
         dev->busy = false;
-        dev->pdev = pdev;
-        platform_set_drvdata(pdev, dev);
-
-        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        if (!res) {
-                ret = -ENOENT;
-                goto err_no_resource;
-        }
+        dev->adev = adev;
+        amba_set_drvdata(adev, dev);
 
-        if (request_mem_region(res->start, resource_size(res),
-                DRIVER_NAME "I/O region") == NULL) {
-                ret = -EBUSY;
-                goto err_no_region;
-        }
-
-        dev->virtbase = ioremap(res->start, resource_size(res));
+        dev->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
         if (!dev->virtbase) {
                 ret = -ENOMEM;
                 goto err_no_ioremap;
         }
 
-        dev->irq = platform_get_irq(pdev, 0);
+        dev->irq = adev->irq[0];
         ret = request_irq(dev->irq, i2c_irq_handler, 0,
                                 DRIVER_NAME, dev);
         if (ret) {
-                dev_err(&pdev->dev, "cannot claim the irq %d\n", dev->irq);
+                dev_err(&adev->dev, "cannot claim the irq %d\n", dev->irq);
                 goto err_irq;
         }
 
-        dev->regulator = regulator_get(&pdev->dev, "v-i2c");
+        dev->regulator = regulator_get(&adev->dev, "v-i2c");
         if (IS_ERR(dev->regulator)) {
-                dev_warn(&pdev->dev, "could not get i2c regulator\n");
+                dev_warn(&adev->dev, "could not get i2c regulator\n");
                 dev->regulator = NULL;
         }
 
-        pm_suspend_ignore_children(&pdev->dev, true);
-        pm_runtime_enable(&pdev->dev);
+        pm_suspend_ignore_children(&adev->dev, true);
 
-        dev->clk = clk_get(&pdev->dev, NULL);
+        dev->clk = clk_get(&adev->dev, NULL);
         if (IS_ERR(dev->clk)) {
-                dev_err(&pdev->dev, "could not get i2c clock\n");
+                dev_err(&adev->dev, "could not get i2c clock\n");
                 ret = PTR_ERR(dev->clk);
                 goto err_no_clk;
         }
 
         adap = &dev->adap;
-        adap->dev.parent = &pdev->dev;
+        adap->dev.parent = &adev->dev;
         adap->owner     = THIS_MODULE;
         adap->class     = I2C_CLASS_HWMON | I2C_CLASS_SPD;
         adap->algo      = &nmk_i2c_algo;
         adap->timeout   = pdata->timeout ? msecs_to_jiffies(pdata->timeout) :
                 msecs_to_jiffies(20000);
+        adap->nr = atomic_read(&adapter_id);
         snprintf(adap->name, sizeof(adap->name),
-                 "Nomadik I2C%d at %lx", pdev->id, (unsigned long)res->start);
-
-        /* fetch the controller id */
-        adap->nr        = pdev->id;
+                 "Nomadik I2C%d at %pR", adap->nr, &adev->res);
+        atomic_inc(&adapter_id);
 
         /* fetch the controller configuration from machine */
         dev->cfg.clk_freq = pdata->clk_freq;
@@ -981,16 +973,18 @@ static int __devinit nmk_i2c_probe(struct platform_device *pdev)
 
         i2c_set_adapdata(adap, dev);
 
-        dev_info(&pdev->dev,
+        dev_info(&adev->dev,
                  "initialize %s on virtual base %p\n",
                  adap->name, dev->virtbase);
 
         ret = i2c_add_numbered_adapter(adap);
         if (ret) {
-                dev_err(&pdev->dev, "failed to add adapter\n");
+                dev_err(&adev->dev, "failed to add adapter\n");
                 goto err_add_adap;
         }
 
+        pm_runtime_put(&adev->dev);
+
         return 0;
 
  err_add_adap:
@@ -998,25 +992,21 @@ static int __devinit nmk_i2c_probe(struct platform_device *pdev)
  err_no_clk:
         if (dev->regulator)
                 regulator_put(dev->regulator);
-        pm_runtime_disable(&pdev->dev);
         free_irq(dev->irq, dev);
  err_irq:
         iounmap(dev->virtbase);
  err_no_ioremap:
-        release_mem_region(res->start, resource_size(res));
- err_no_region:
-        platform_set_drvdata(pdev, NULL);
- err_no_resource:
+        amba_set_drvdata(adev, NULL);
         kfree(dev);
  err_no_mem:
 
         return ret;
 }
 
-static int __devexit nmk_i2c_remove(struct platform_device *pdev)
+static int nmk_i2c_remove(struct amba_device *adev)
 {
-        struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        struct nmk_i2c_dev *dev = platform_get_drvdata(pdev);
+        struct resource *res = &adev->res;
+        struct nmk_i2c_dev *dev = amba_get_drvdata(adev);
 
         i2c_del_adapter(&dev->adap);
         flush_i2c_fifo(dev);
@@ -1031,31 +1021,46 @@ static int __devexit nmk_i2c_remove(struct platform_device *pdev)
         clk_put(dev->clk);
         if (dev->regulator)
                 regulator_put(dev->regulator);
-        pm_runtime_disable(&pdev->dev);
-        platform_set_drvdata(pdev, NULL);
+        pm_runtime_disable(&adev->dev);
+        amba_set_drvdata(adev, NULL);
         kfree(dev);
 
         return 0;
 }
 
-static struct platform_driver nmk_i2c_driver = {
-        .driver = {
+static struct amba_id nmk_i2c_ids[] = {
+        {
+                .id     = 0x00180024,
+                .mask   = 0x00ffffff,
+        },
+        {
+                .id     = 0x00380024,
+                .mask   = 0x00ffffff,
+        },
+        {},
+};
+
+MODULE_DEVICE_TABLE(amba, nmk_i2c_ids);
+
+static struct amba_driver nmk_i2c_driver = {
+        .drv = {
                 .owner = THIS_MODULE,
                 .name = DRIVER_NAME,
                 .pm = &nmk_i2c_pm,
         },
+        .id_table = nmk_i2c_ids,
         .probe = nmk_i2c_probe,
-        .remove = __devexit_p(nmk_i2c_remove),
+        .remove = nmk_i2c_remove,
 };
 
 static int __init nmk_i2c_init(void)
 {
-        return platform_driver_register(&nmk_i2c_driver);
+        return amba_driver_register(&nmk_i2c_driver);
 }
 
 static void __exit nmk_i2c_exit(void)
 {
-        platform_driver_unregister(&nmk_i2c_driver);
+        amba_driver_unregister(&nmk_i2c_driver);
 }
 
 subsys_initcall(nmk_i2c_init);
@@ -1064,4 +1069,3 @@ module_exit(nmk_i2c_exit);
 MODULE_AUTHOR("Sachin Verma, Srinidhi KASAGAR");
 MODULE_DESCRIPTION("Nomadik/Ux500 I2C driver");
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:" DRIVER_NAME);