spi_mpc83xx: add OF platform driver bindings

Implement full support for OF SPI bindings.  Now the driver can manage its
own chip selects without any help from the board files and/or fsl_soc
constructors.

The "legacy" code is well isolated and could be removed as time goes by.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 294 insertions, 36 deletions

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index b95085a46f90..f4573a96af24 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -14,6 +14,8 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
 #include <linux/completion.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
@@ -23,7 +25,13 @@
 #include <linux/spi/spi_bitbang.h>
 #include <linux/platform_device.h>
 #include <linux/fsl_devices.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/gpio.h>
+#include <linux/of_gpio.h>
+#include <linux/of_spi.h>
 
+#include <sysdev/fsl_soc.h>
 #include <asm/irq.h>
 #include <asm/io.h>
 
@@ -79,7 +87,7 @@ struct mpc83xx_spi {
         u32(*get_tx) (struct mpc83xx_spi *);
 
         unsigned int count;
-        int irq;
+        unsigned int irq;
 
         unsigned nsecs;         /* (clock cycle time)/2 */
 
@@ -543,36 +551,23 @@ static void mpc83xx_spi_cleanup(struct spi_device *spi)
         kfree(spi->controller_state);
 }
 
-static int __init mpc83xx_spi_probe(struct platform_device *dev)
+static struct spi_master * __devinit
+mpc83xx_spi_probe(struct device *dev, struct resource *mem, unsigned int irq)
 {
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
         struct spi_master *master;
         struct mpc83xx_spi *mpc83xx_spi;
-        struct fsl_spi_platform_data *pdata;
-        struct resource *r;
         u32 regval;
         int ret = 0;
 
-        /* Get resources(memory, IRQ) associated with the device */
-        master = spi_alloc_master(&dev->dev, sizeof(struct mpc83xx_spi));
-
+        master = spi_alloc_master(dev, sizeof(struct mpc83xx_spi));
         if (master == NULL) {
                 ret = -ENOMEM;
                 goto err;
         }
 
-        platform_set_drvdata(dev, master);
-        pdata = dev->dev.platform_data;
-
-        if (pdata == NULL) {
-                ret = -ENODEV;
-                goto free_master;
-        }
+        dev_set_drvdata(dev, master);
 
-        r = platform_get_resource(dev, IORESOURCE_MEM, 0);
-        if (r == NULL) {
-                ret = -ENODEV;
-                goto free_master;
-        }
         master->setup = mpc83xx_spi_setup;
         master->transfer = mpc83xx_spi_transfer;
         master->cleanup = mpc83xx_spi_cleanup;
@@ -592,18 +587,13 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
 
         init_completion(&mpc83xx_spi->done);
 
-        mpc83xx_spi->base = ioremap(r->start, r->end - r->start + 1);
+        mpc83xx_spi->base = ioremap(mem->start, mem->end - mem->start + 1);
         if (mpc83xx_spi->base == NULL) {
                 ret = -ENOMEM;
                 goto put_master;
         }
 
-        mpc83xx_spi->irq = platform_get_irq(dev, 0);
-
-        if (mpc83xx_spi->irq < 0) {
-                ret = -ENXIO;
-                goto unmap_io;
-        }
+        mpc83xx_spi->irq = irq;
 
         /* Register for SPI Interrupt */
         ret = request_irq(mpc83xx_spi->irq, mpc83xx_spi_irq,
@@ -645,9 +635,9 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev)
 
         printk(KERN_INFO
                "%s: MPC83xx SPI Controller driver at 0x%p (irq = %d)\n",
-               dev_name(&dev->dev), mpc83xx_spi->base, mpc83xx_spi->irq);
+               dev_name(dev), mpc83xx_spi->base, mpc83xx_spi->irq);
 
-        return ret;
+        return master;
 
 unreg_master:
         destroy_workqueue(mpc83xx_spi->workqueue);
@@ -657,18 +647,16 @@ unmap_io:
         iounmap(mpc83xx_spi->base);
 put_master:
         spi_master_put(master);
-free_master:
-        kfree(master);
 err:
-        return ret;
+        return ERR_PTR(ret);
 }
 
-static int __exit mpc83xx_spi_remove(struct platform_device *dev)
+static int __devexit mpc83xx_spi_remove(struct device *dev)
 {
         struct mpc83xx_spi *mpc83xx_spi;
         struct spi_master *master;
 
-        master = platform_get_drvdata(dev);
+        master = dev_get_drvdata(dev);
         mpc83xx_spi = spi_master_get_devdata(master);
 
         flush_workqueue(mpc83xx_spi->workqueue);
@@ -681,23 +669,293 @@ static int __exit mpc83xx_spi_remove(struct platform_device *dev)
         return 0;
 }
 
+struct mpc83xx_spi_probe_info {
+        struct fsl_spi_platform_data pdata;
+        int *gpios;
+        bool *alow_flags;
+};
+
+static struct mpc83xx_spi_probe_info *
+to_of_pinfo(struct fsl_spi_platform_data *pdata)
+{
+        return container_of(pdata, struct mpc83xx_spi_probe_info, pdata);
+}
+
+static void mpc83xx_spi_cs_control(struct spi_device *spi, bool on)
+{
+        struct device *dev = spi->dev.parent;
+        struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(dev->platform_data);
+        u16 cs = spi->chip_select;
+        int gpio = pinfo->gpios[cs];
+        bool alow = pinfo->alow_flags[cs];
+
+        gpio_set_value(gpio, on ^ alow);
+}
+
+static int of_mpc83xx_spi_get_chipselects(struct device *dev)
+{
+        struct device_node *np = dev_archdata_get_node(&dev->archdata);
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
+        struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+        unsigned int ngpios;
+        int i = 0;
+        int ret;
+
+        ngpios = of_gpio_count(np);
+        if (!ngpios) {
+                /*
+                 * SPI w/o chip-select line. One SPI device is still permitted
+                 * though.
+                 */
+                pdata->max_chipselect = 1;
+                return 0;
+        }
+
+        pinfo->gpios = kmalloc(ngpios * sizeof(pinfo->gpios), GFP_KERNEL);
+        if (!pinfo->gpios)
+                return -ENOMEM;
+        memset(pinfo->gpios, -1, ngpios * sizeof(pinfo->gpios));
+
+        pinfo->alow_flags = kzalloc(ngpios * sizeof(pinfo->alow_flags),
+                                    GFP_KERNEL);
+        if (!pinfo->alow_flags) {
+                ret = -ENOMEM;
+                goto err_alloc_flags;
+        }
+
+        for (; i < ngpios; i++) {
+                int gpio;
+                enum of_gpio_flags flags;
+
+                gpio = of_get_gpio_flags(np, i, &flags);
+                if (!gpio_is_valid(gpio)) {
+                        dev_err(dev, "invalid gpio #%d: %d\n", i, gpio);
+                        goto err_loop;
+                }
+
+                ret = gpio_request(gpio, dev_name(dev));
+                if (ret) {
+                        dev_err(dev, "can't request gpio #%d: %d\n", i, ret);
+                        goto err_loop;
+                }
+
+                pinfo->gpios[i] = gpio;
+                pinfo->alow_flags[i] = flags & OF_GPIO_ACTIVE_LOW;
+
+                ret = gpio_direction_output(pinfo->gpios[i],
+                                            pinfo->alow_flags[i]);
+                if (ret) {
+                        dev_err(dev, "can't set output direction for gpio "
+                                "#%d: %d\n", i, ret);
+                        goto err_loop;
+                }
+        }
+
+        pdata->max_chipselect = ngpios;
+        pdata->cs_control = mpc83xx_spi_cs_control;
+
+        return 0;
+
+err_loop:
+        while (i >= 0) {
+                if (gpio_is_valid(pinfo->gpios[i]))
+                        gpio_free(pinfo->gpios[i]);
+                i--;
+        }
+
+        kfree(pinfo->alow_flags);
+        pinfo->alow_flags = NULL;
+err_alloc_flags:
+        kfree(pinfo->gpios);
+        pinfo->gpios = NULL;
+        return ret;
+}
+
+static int of_mpc83xx_spi_free_chipselects(struct device *dev)
+{
+        struct fsl_spi_platform_data *pdata = dev->platform_data;
+        struct mpc83xx_spi_probe_info *pinfo = to_of_pinfo(pdata);
+        int i;
+
+        if (!pinfo->gpios)
+                return 0;
+
+        for (i = 0; i < pdata->max_chipselect; i++) {
+                if (gpio_is_valid(pinfo->gpios[i]))
+                        gpio_free(pinfo->gpios[i]);
+        }
+
+        kfree(pinfo->gpios);
+        kfree(pinfo->alow_flags);
+        return 0;
+}
+
+static int __devinit of_mpc83xx_spi_probe(struct of_device *ofdev,
+                                          const struct of_device_id *ofid)
+{
+        struct device *dev = &ofdev->dev;
+        struct device_node *np = ofdev->node;
+        struct mpc83xx_spi_probe_info *pinfo;
+        struct fsl_spi_platform_data *pdata;
+        struct spi_master *master;
+        struct resource mem;
+        struct resource irq;
+        const void *prop;
+        int ret = -ENOMEM;
+
+        pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
+        if (!pinfo)
+                return -ENOMEM;
+
+        pdata = &pinfo->pdata;
+        dev->platform_data = pdata;
+
+        /* Allocate bus num dynamically. */
+        pdata->bus_num = -1;
+
+        /* SPI controller is either clocked from QE or SoC clock. */
+        pdata->sysclk = get_brgfreq();
+        if (pdata->sysclk == -1) {
+                pdata->sysclk = fsl_get_sys_freq();
+                if (pdata->sysclk == -1) {
+                        ret = -ENODEV;
+                        goto err_clk;
+                }
+        }
+
+        prop = of_get_property(np, "mode", NULL);
+        if (prop && !strcmp(prop, "cpu-qe"))
+                pdata->qe_mode = 1;
+
+        ret = of_mpc83xx_spi_get_chipselects(dev);
+        if (ret)
+                goto err;
+
+        ret = of_address_to_resource(np, 0, &mem);
+        if (ret)
+                goto err;
+
+        ret = of_irq_to_resource(np, 0, &irq);
+        if (!ret) {
+                ret = -EINVAL;
+                goto err;
+        }
+
+        master = mpc83xx_spi_probe(dev, &mem, irq.start);
+        if (IS_ERR(master)) {
+                ret = PTR_ERR(master);
+                goto err;
+        }
+
+        of_register_spi_devices(master, np);
+
+        return 0;
+
+err:
+        of_mpc83xx_spi_free_chipselects(dev);
+err_clk:
+        kfree(pinfo);
+        return ret;
+}
+
+static int __devexit of_mpc83xx_spi_remove(struct of_device *ofdev)
+{
+        int ret;
+
+        ret = mpc83xx_spi_remove(&ofdev->dev);
+        if (ret)
+                return ret;
+        of_mpc83xx_spi_free_chipselects(&ofdev->dev);
+        return 0;
+}
+
+static const struct of_device_id of_mpc83xx_spi_match[] = {
+        { .compatible = "fsl,spi" },
+        {},
+};
+MODULE_DEVICE_TABLE(of, of_mpc83xx_spi_match);
+
+static struct of_platform_driver of_mpc83xx_spi_driver = {
+        .name           = "mpc83xx_spi",
+        .match_table    = of_mpc83xx_spi_match,
+        .probe          = of_mpc83xx_spi_probe,
+        .remove         = __devexit_p(of_mpc83xx_spi_remove),
+};
+
+#ifdef CONFIG_MPC832x_RDB
+/*
+ *                              XXX XXX XXX
+ * This is "legacy" platform driver, was used by the MPC8323E-RDB boards
+ * only. The driver should go away soon, since newer MPC8323E-RDB's device
+ * tree can work with OpenFirmware driver. But for now we support old trees
+ * as well.
+ */
+static int __devinit plat_mpc83xx_spi_probe(struct platform_device *pdev)
+{
+        struct resource *mem;
+        unsigned int irq;
+        struct spi_master *master;
+
+        if (!pdev->dev.platform_data)
+                return -EINVAL;
+
+        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!mem)
+                return -EINVAL;
+
+        irq = platform_get_irq(pdev, 0);
+        if (!irq)
+                return -EINVAL;
+
+        master = mpc83xx_spi_probe(&pdev->dev, mem, irq);
+        if (IS_ERR(master))
+                return PTR_ERR(master);
+        return 0;
+}
+
+static int __devexit plat_mpc83xx_spi_remove(struct platform_device *pdev)
+{
+        return mpc83xx_spi_remove(&pdev->dev);
+}
+
 MODULE_ALIAS("platform:mpc83xx_spi");
 static struct platform_driver mpc83xx_spi_driver = {
-        .remove = __exit_p(mpc83xx_spi_remove),
+        .probe = plat_mpc83xx_spi_probe,
+        .remove = __exit_p(plat_mpc83xx_spi_remove),
         .driver = {
                 .name = "mpc83xx_spi",
                 .owner = THIS_MODULE,
         },
 };
 
+static bool legacy_driver_failed;
+
+static void __init legacy_driver_register(void)
+{
+        legacy_driver_failed = platform_driver_register(&mpc83xx_spi_driver);
+}
+
+static void __exit legacy_driver_unregister(void)
+{
+        if (legacy_driver_failed)
+                return;
+        platform_driver_unregister(&mpc83xx_spi_driver);
+}
+#else
+static void __init legacy_driver_register(void) {}
+static void __exit legacy_driver_unregister(void) {}
+#endif /* CONFIG_MPC832x_RDB */
+
 static int __init mpc83xx_spi_init(void)
 {
-        return platform_driver_probe(&mpc83xx_spi_driver, mpc83xx_spi_probe);
+        legacy_driver_register();
+        return of_register_platform_driver(&of_mpc83xx_spi_driver);
 }
 
 static void __exit mpc83xx_spi_exit(void)
 {
-        platform_driver_unregister(&mpc83xx_spi_driver);
+        of_unregister_platform_driver(&of_mpc83xx_spi_driver);
+        legacy_driver_unregister();
 }
 
 module_init(mpc83xx_spi_init);