Re: [PATCH] i2c: pxa: create dynamic platform device from device tree
From: Grant Likely <hidden>
Date: 2011-07-10 05:26:21
Also in:
linux-arm-kernel
On Fri, Jul 08, 2011 at 06:20:23PM +0800, Haojian Zhuang wrote:
quoted hunk
Create two probe function to support both current platform device and created dynamic platform device from device tree. After moving to device tree, original implementation of platform device will be removed. Use property to present polling mode and frequency mode. Signed-off-by: Haojian Zhuang <redacted> --- drivers/i2c/busses/i2c-pxa.c | 163 ++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 163 insertions(+), 0 deletions(-)diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index d603646..7a6d774 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c@@ -29,6 +29,7 @@ #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/i2c-pxa.h> +#include <linux/of_device.h> #include <linux/of_i2c.h> #include <linux/platform_device.h> #include <linux/err.h>@@ -1044,6 +1045,162 @@ static const struct i2c_algorithm i2c_pxa_pio_algorithm = { .functionality = i2c_pxa_functionality, }; +static const struct of_device_id pxa_i2c_of_match[] = { + { .compatible = "pxa2xx-i2c", .data = (void *)REGS_PXA2XX, }, + { .compatible = "pxa3xx-pwri2c", .data = (void *)REGS_PXA3XX, }, + { .compatible = "ce4100-i2c", .data = (void *)REGS_CE4100, },
New compatible values need to be written up in Documentation/devicetree/bindings, and strings should be in the form "<vendor>,<soc>-i2c". They should also be specific to the soc instead of trying to be generic (ie. use "marvell,pxa255-i2c" instead of "marvell,pxa2xx-i2c".
+ {},
+};
+
+#ifdef CONFIG_OF
+static int i2c_pxa_of_probe(struct platform_device *of_dev)
+{CONFIG_OF should not be an either/or option. Turning on CONFIG_OF must not disable non-DT users.
+ struct device_node *np = of_dev->dev.of_node; + const struct of_device_id *match; + struct i2c_pxa_platform_data *plat = NULL; + struct pxa_i2c *i2c; + struct resource *res; + const __be32 *p; + int i2c_type, irq, data, ret; + int id = 0, poll = 0, fast = 0; + + match = of_match_device(pxa_i2c_of_match, &of_dev->dev); + if (match == NULL) + return -ENODEV; + i2c_type = (int)match->data; + + p = of_get_property(np, "cell-index", &data); + if (p) + id = be32_to_cpu(*p);
When using the device tree, the bus id should be dynamically assigned. Don't use a cell-index property.
+ + p = of_get_property(np, "i2c-polling", &data); + if (p) + poll = be32_to_cpu(*p); + + p = of_get_property(np, "i2c-frequency", &data); + if (p && !strncmp((char *)p, "fast", data)) + fast = 1; + + res = platform_get_resource(of_dev, IORESOURCE_MEM, 0); + irq = platform_get_irq(of_dev, 0); + if (res == NULL || irq < 0) + return -ENODEV; + + if (!request_mem_region(res->start, resource_size(res), res->name)) + return -ENOMEM; + + i2c = kzalloc(sizeof(struct pxa_i2c), GFP_KERNEL);
kzalloc(sizeof(*i2c), GFP_KERNEL)
quoted hunk
+ if (!i2c) { + ret = -ENOMEM; + goto emalloc; + } + + i2c->adap.owner = THIS_MODULE; + i2c->adap.retries = 5; + + spin_lock_init(&i2c->lock); + init_waitqueue_head(&i2c->wait); + + /* + * adap.nr comes from cell-index in dts file + */ + i2c->adap.nr = id; + snprintf(i2c->adap.name, sizeof(i2c->adap.name), "pxa2xx-i2c.%u", + i2c->adap.nr); + + i2c->clk = clk_get_sys(i2c->adap.name, NULL); + if (IS_ERR(i2c->clk)) { + ret = PTR_ERR(i2c->clk); + goto eclk; + } + + i2c->reg_base = ioremap(res->start, resource_size(res)); + if (!i2c->reg_base) { + ret = -EIO; + goto eremap; + } + + i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr; + i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr; + i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr; + i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr; + if (i2c_type != REGS_CE4100) + i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar; + + i2c->iobase = res->start; + i2c->iosize = resource_size(res); + + i2c->irq = irq; + i2c->use_pio = poll; + i2c->fast_mode = fast; + + i2c->slave_addr = I2C_PXA_SLAVE_ADDR; + +#ifdef CONFIG_I2C_PXA_SLAVE + if (plat) { + i2c->slave_addr = plat->slave_addr; + i2c->slave = plat->slave; + } +#endif + + clk_enable(i2c->clk); + + if (plat) + i2c->adap.class = plat->class; + + if (i2c->use_pio) { + i2c->adap.algo = &i2c_pxa_pio_algorithm; + } else { + i2c->adap.algo = &i2c_pxa_algorithm; + ret = request_irq(irq, i2c_pxa_handler, IRQF_SHARED, + i2c->adap.name, i2c); + if (ret) + goto ereqirq; + } + + i2c_pxa_reset(i2c); + + i2c->adap.algo_data = i2c; + i2c->adap.dev.parent = &of_dev->dev; + i2c->adap.dev.of_node = of_dev->dev.of_node; + + if (i2c_type == REGS_CE4100) + ret = i2c_add_adapter(&i2c->adap); + else + ret = i2c_add_numbered_adapter(&i2c->adap); + if (ret < 0) { + printk(KERN_INFO "I2C: Failed to add bus\n"); + goto eadapt; + } + of_i2c_register_devices(&i2c->adap); + + platform_set_drvdata(of_dev, i2c); + +#ifdef CONFIG_I2C_PXA_SLAVE + printk(KERN_INFO "I2C: %s: PXA I2C adapter, slave address %d\n", + dev_name(&i2c->adap.dev), i2c->slave_addr); +#else + printk(KERN_INFO "I2C: %s: PXA I2C adapter\n", + dev_name(&i2c->adap.dev)); +#endif + return 0; + +eadapt: + if (!i2c->use_pio) + free_irq(irq, i2c); +ereqirq: + clk_disable(i2c->clk); + iounmap(i2c->reg_base); +eremap: + clk_put(i2c->clk); +eclk: + kfree(i2c); +emalloc: + release_mem_region(res->start, resource_size(res)); + return ret; +} +#else + static int i2c_pxa_probe(struct platform_device *dev) { struct pxa_i2c *i2c;@@ -1174,6 +1331,7 @@ emalloc: release_mem_region(res->start, resource_size(res)); return ret; } +#endif static int __exit i2c_pxa_remove(struct platform_device *dev) {@@ -1228,12 +1386,17 @@ static const struct dev_pm_ops i2c_pxa_dev_pm_ops = { #endif static struct platform_driver i2c_pxa_driver = { +#ifdef CONFIG_OF + .probe = i2c_pxa_of_probe, +#else .probe = i2c_pxa_probe, +#endif .remove = __exit_p(i2c_pxa_remove), .driver = { .name = "pxa2xx-i2c", .owner = THIS_MODULE, .pm = I2C_PXA_DEV_PM_OPS, + .of_match_table = pxa_i2c_of_match, }, .id_table = i2c_pxa_id_table, };-- 1.5.6.5