Date:	Fri, 23 Jan 2009 22:50:35 +0300
From:	Anton Vorontsov <avorontsov@...mvista.com>
To:	David Brownell <dbrownell@...rs.sourceforge.net>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Kumar Gala <galak@...nel.crashing.org>,
	Grant Likely <grant.likely@...retlab.ca>,
	linuxppc-dev@...abs.org, spi-devel-general@...ts.sourceforge.net,
	linux-kernel@...r.kernel.org
Subject: [PATCH 3/6] spi_mpc83xx: Add OF platform driver bindings

This patch implements 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@...mvista.com>
---
 drivers/spi/spi_mpc83xx.c   |  330 ++++++++++++++++++++++++++++++++++++++-----
 include/linux/fsl_devices.h |    2 +-
 2 files changed, 295 insertions(+), 37 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 056d200..09081bb 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->dev.bus_id, 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);
diff --git a/include/linux/fsl_devices.h b/include/linux/fsl_devices.h
index 7bc1b64..7ef1caf 100644
--- a/include/linux/fsl_devices.h
+++ b/include/linux/fsl_devices.h
@@ -99,7 +99,7 @@ struct spi_device;
 
 struct fsl_spi_platform_data {
 	u32 	initial_spmode;	/* initial SPMODE value */
-	u16	bus_num;
+	s16	bus_num;
 	bool	qe_mode;
 	/* board specific information */
 	u16	max_chipselect;
-- 
1.5.6.5

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