diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-ocores.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-ocores.c | 293 |
1 files changed, 206 insertions, 87 deletions
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c index 0070371b29f..0e10cc6182f 100644 --- a/drivers/i2c/busses/i2c-ocores.c +++ b/drivers/i2c/busses/i2c-ocores.c @@ -4,14 +4,17 @@ * * Peter Korsgaard <jacmet@sunsite.dk> * + * Support for the GRLIB port of the controller by + * Andreas Larsson <andreas@gaisler.com> + * * This file is licensed under the terms of the GNU General Public License * version 2. This program is licensed "as is" without any warranty of any * kind, whether express or implied. */ +#include <linux/err.h> #include <linux/kernel.h> #include <linux/module.h> -#include <linux/init.h> #include <linux/errno.h> #include <linux/platform_device.h> #include <linux/i2c.h> @@ -20,10 +23,12 @@ #include <linux/i2c-ocores.h> #include <linux/slab.h> #include <linux/io.h> +#include <linux/log2.h> struct ocores_i2c { void __iomem *base; - int regstep; + u32 reg_shift; + u32 reg_io_width; wait_queue_head_t wait; struct i2c_adapter adap; struct i2c_msg *msg; @@ -31,6 +36,8 @@ struct ocores_i2c { int nmsgs; int state; /* see STATE_ */ int clock_khz; + void (*setreg)(struct ocores_i2c *i2c, int reg, u8 value); + u8 (*getreg)(struct ocores_i2c *i2c, int reg); }; /* registers */ @@ -64,14 +71,47 @@ struct ocores_i2c { #define STATE_READ 3 #define STATE_ERROR 4 +#define TYPE_OCORES 0 +#define TYPE_GRLIB 1 + +static void oc_setreg_8(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite8(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_16(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite16(value, i2c->base + (reg << i2c->reg_shift)); +} + +static void oc_setreg_32(struct ocores_i2c *i2c, int reg, u8 value) +{ + iowrite32(value, i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_8(struct ocores_i2c *i2c, int reg) +{ + return ioread8(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_16(struct ocores_i2c *i2c, int reg) +{ + return ioread16(i2c->base + (reg << i2c->reg_shift)); +} + +static inline u8 oc_getreg_32(struct ocores_i2c *i2c, int reg) +{ + return ioread32(i2c->base + (reg << i2c->reg_shift)); +} + static inline void oc_setreg(struct ocores_i2c *i2c, int reg, u8 value) { - iowrite8(value, i2c->base + reg * i2c->regstep); + i2c->setreg(i2c, reg, value); } static inline u8 oc_getreg(struct ocores_i2c *i2c, int reg) { - return ioread8(i2c->base + reg * i2c->regstep); + return i2c->getreg(i2c, reg); } static void ocores_process(struct ocores_i2c *i2c) @@ -206,58 +246,170 @@ static const struct i2c_algorithm ocores_algorithm = { static struct i2c_adapter ocores_adapter = { .owner = THIS_MODULE, .name = "i2c-ocores", - .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, + .class = I2C_CLASS_HWMON | I2C_CLASS_SPD | I2C_CLASS_DEPRECATED, .algo = &ocores_algorithm, }; +static const struct of_device_id ocores_i2c_match[] = { + { + .compatible = "opencores,i2c-ocores", + .data = (void *)TYPE_OCORES, + }, + { + .compatible = "aeroflexgaisler,i2cmst", + .data = (void *)TYPE_GRLIB, + }, + {}, +}; +MODULE_DEVICE_TABLE(of, ocores_i2c_match); + +#ifdef CONFIG_OF +/* Read and write functions for the GRLIB port of the controller. Registers are + * 32-bit big endian and the PRELOW and PREHIGH registers are merged into one + * register. The subsequent registers has their offset decreased accordingly. */ +static u8 oc_getreg_grlib(struct ocores_i2c *i2c, int reg) +{ + u32 rd; + int rreg = reg; + if (reg != OCI2C_PRELOW) + rreg--; + rd = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PREHIGH) + return (u8)(rd >> 8); + else + return (u8)rd; +} + +static void oc_setreg_grlib(struct ocores_i2c *i2c, int reg, u8 value) +{ + u32 curr, wr; + int rreg = reg; + if (reg != OCI2C_PRELOW) + rreg--; + if (reg == OCI2C_PRELOW || reg == OCI2C_PREHIGH) { + curr = ioread32be(i2c->base + (rreg << i2c->reg_shift)); + if (reg == OCI2C_PRELOW) + wr = (curr & 0xff00) | value; + else + wr = (((u32)value) << 8) | (curr & 0xff); + } else { + wr = value; + } + iowrite32be(wr, i2c->base + (rreg << i2c->reg_shift)); +} + +static int ocores_i2c_of_probe(struct platform_device *pdev, + struct ocores_i2c *i2c) +{ + struct device_node *np = pdev->dev.of_node; + const struct of_device_id *match; + u32 val; + + if (of_property_read_u32(np, "reg-shift", &i2c->reg_shift)) { + /* no 'reg-shift', check for deprecated 'regstep' */ + if (!of_property_read_u32(np, "regstep", &val)) { + if (!is_power_of_2(val)) { + dev_err(&pdev->dev, "invalid regstep %d\n", + val); + return -EINVAL; + } + i2c->reg_shift = ilog2(val); + dev_warn(&pdev->dev, + "regstep property deprecated, use reg-shift\n"); + } + } + + if (of_property_read_u32(np, "clock-frequency", &val)) { + dev_err(&pdev->dev, + "Missing required parameter 'clock-frequency'\n"); + return -ENODEV; + } + i2c->clock_khz = val / 1000; + + of_property_read_u32(pdev->dev.of_node, "reg-io-width", + &i2c->reg_io_width); + + match = of_match_node(ocores_i2c_match, pdev->dev.of_node); + if (match && (long)match->data == TYPE_GRLIB) { + dev_dbg(&pdev->dev, "GRLIB variant of i2c-ocores\n"); + i2c->setreg = oc_setreg_grlib; + i2c->getreg = oc_getreg_grlib; + } + + return 0; +} +#else +#define ocores_i2c_of_probe(pdev,i2c) -ENODEV +#endif -static int __devinit ocores_i2c_probe(struct platform_device *pdev) +static int ocores_i2c_probe(struct platform_device *pdev) { struct ocores_i2c *i2c; struct ocores_i2c_platform_data *pdata; - struct resource *res, *res2; + struct resource *res; + int irq; int ret; int i; - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) - return -ENODEV; - - res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0); - if (!res2) - return -ENODEV; - - pdata = (struct ocores_i2c_platform_data*) pdev->dev.platform_data; - if (!pdata) - return -ENODEV; + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; - i2c = kzalloc(sizeof(*i2c), GFP_KERNEL); + i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); if (!i2c) return -ENOMEM; - if (!request_mem_region(res->start, resource_size(res), - pdev->name)) { - dev_err(&pdev->dev, "Memory region busy\n"); - ret = -EBUSY; - goto request_mem_failed; + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + i2c->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + i2c->reg_shift = pdata->reg_shift; + i2c->reg_io_width = pdata->reg_io_width; + i2c->clock_khz = pdata->clock_khz; + } else { + ret = ocores_i2c_of_probe(pdev, i2c); + if (ret) + return ret; } - i2c->base = ioremap(res->start, resource_size(res)); - if (!i2c->base) { - dev_err(&pdev->dev, "Unable to map registers\n"); - ret = -EIO; - goto map_failed; + if (i2c->reg_io_width == 0) + i2c->reg_io_width = 1; /* Set to default value */ + + if (!i2c->setreg || !i2c->getreg) { + switch (i2c->reg_io_width) { + case 1: + i2c->setreg = oc_setreg_8; + i2c->getreg = oc_getreg_8; + break; + + case 2: + i2c->setreg = oc_setreg_16; + i2c->getreg = oc_getreg_16; + break; + + case 4: + i2c->setreg = oc_setreg_32; + i2c->getreg = oc_getreg_32; + break; + + default: + dev_err(&pdev->dev, "Unsupported I/O width (%d)\n", + i2c->reg_io_width); + return -EINVAL; + } } - i2c->regstep = pdata->regstep; - i2c->clock_khz = pdata->clock_khz; ocores_init(i2c); init_waitqueue_head(&i2c->wait); - ret = request_irq(res2->start, ocores_isr, 0, pdev->name, i2c); + ret = devm_request_irq(&pdev->dev, irq, ocores_isr, 0, + pdev->name, i2c); if (ret) { dev_err(&pdev->dev, "Cannot claim IRQ\n"); - goto request_irq_failed; + return ret; } /* hook up driver to tree */ @@ -265,36 +417,27 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev) i2c->adap = ocores_adapter; i2c_set_adapdata(&i2c->adap, i2c); i2c->adap.dev.parent = &pdev->dev; + i2c->adap.dev.of_node = pdev->dev.of_node; /* add i2c adapter to i2c tree */ ret = i2c_add_adapter(&i2c->adap); if (ret) { dev_err(&pdev->dev, "Failed to add adapter\n"); - goto add_adapter_failed; + return ret; } /* add in known devices to the bus */ - for (i = 0; i < pdata->num_devices; i++) - i2c_new_device(&i2c->adap, pdata->devices + i); + if (pdata) { + for (i = 0; i < pdata->num_devices; i++) + i2c_new_device(&i2c->adap, pdata->devices + i); + } return 0; - -add_adapter_failed: - free_irq(res2->start, i2c); -request_irq_failed: - iounmap(i2c->base); -map_failed: - release_mem_region(res->start, resource_size(res)); -request_mem_failed: - kfree(i2c); - - return ret; } -static int __devexit ocores_i2c_remove(struct platform_device* pdev) +static int ocores_i2c_remove(struct platform_device *pdev) { struct ocores_i2c *i2c = platform_get_drvdata(pdev); - struct resource *res; /* disable i2c logic */ oc_setreg(i2c, OCI2C_CONTROL, oc_getreg(i2c, OCI2C_CONTROL) @@ -302,27 +445,14 @@ static int __devexit ocores_i2c_remove(struct platform_device* pdev) /* remove adapter & data */ i2c_del_adapter(&i2c->adap); - platform_set_drvdata(pdev, NULL); - - res = platform_get_resource(pdev, IORESOURCE_IRQ, 0); - if (res) - free_irq(res->start, i2c); - - iounmap(i2c->base); - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (res) - release_mem_region(res->start, resource_size(res)); - - kfree(i2c); return 0; } -#ifdef CONFIG_PM -static int ocores_i2c_suspend(struct platform_device *pdev, pm_message_t state) +#ifdef CONFIG_PM_SLEEP +static int ocores_i2c_suspend(struct device *dev) { - struct ocores_i2c *i2c = platform_get_drvdata(pdev); + struct ocores_i2c *i2c = dev_get_drvdata(dev); u8 ctrl = oc_getreg(i2c, OCI2C_CONTROL); /* make sure the device is disabled */ @@ -331,46 +461,35 @@ static int ocores_i2c_suspend(struct platform_device *pdev, pm_message_t state) return 0; } -static int ocores_i2c_resume(struct platform_device *pdev) +static int ocores_i2c_resume(struct device *dev) { - struct ocores_i2c *i2c = platform_get_drvdata(pdev); + struct ocores_i2c *i2c = dev_get_drvdata(dev); ocores_init(i2c); return 0; } + +static SIMPLE_DEV_PM_OPS(ocores_i2c_pm, ocores_i2c_suspend, ocores_i2c_resume); +#define OCORES_I2C_PM (&ocores_i2c_pm) #else -#define ocores_i2c_suspend NULL -#define ocores_i2c_resume NULL +#define OCORES_I2C_PM NULL #endif -/* work with hotplug and coldplug */ -MODULE_ALIAS("platform:ocores-i2c"); - static struct platform_driver ocores_i2c_driver = { .probe = ocores_i2c_probe, - .remove = __devexit_p(ocores_i2c_remove), - .suspend = ocores_i2c_suspend, - .resume = ocores_i2c_resume, + .remove = ocores_i2c_remove, .driver = { .owner = THIS_MODULE, .name = "ocores-i2c", + .of_match_table = ocores_i2c_match, + .pm = OCORES_I2C_PM, }, }; -static int __init ocores_i2c_init(void) -{ - return platform_driver_register(&ocores_i2c_driver); -} - -static void __exit ocores_i2c_exit(void) -{ - platform_driver_unregister(&ocores_i2c_driver); -} - -module_init(ocores_i2c_init); -module_exit(ocores_i2c_exit); +module_platform_driver(ocores_i2c_driver); MODULE_AUTHOR("Peter Korsgaard <jacmet@sunsite.dk>"); MODULE_DESCRIPTION("OpenCores I2C bus driver"); MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ocores-i2c"); |