*
* History:
* Apr 2002: Initial version [CS]
- * Jun 2002: Properly seperated algo/adap [FB]
+ * Jun 2002: Properly separated algo/adap [FB]
* Jan 2003: Fixed several bugs concerning interrupt handling [Kai-Uwe Bloem]
* Jan 2003: added limited signal handling [Kai-Uwe Bloem]
* Sep 2004: Major rework to ensure efficient bus handling [RMK]
#include <linux/interrupt.h>
#include <linux/i2c-pxa.h>
#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
-#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/io.h>
-#include <asm/arch/i2c.h>
-#include <asm/arch/pxa-regs.h>
+#include <plat/i2c.h>
+
+/*
+ * I2C register offsets will be shifted 0 or 1 bit left, depending on
+ * different SoCs
+ */
+#define REG_SHIFT_0 (0 << 0)
+#define REG_SHIFT_1 (1 << 0)
+#define REG_SHIFT(d) ((d) & 0x1)
+
+static const struct platform_device_id i2c_pxa_id_table[] = {
+ { "pxa2xx-i2c", REG_SHIFT_1 },
+ { "pxa3xx-pwri2c", REG_SHIFT_0 },
+ { },
+};
+MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
+
+/*
+ * I2C registers and bit definitions
+ */
+#define IBMR (0x00)
+#define IDBR (0x08)
+#define ICR (0x10)
+#define ISR (0x18)
+#define ISAR (0x20)
+
+#define ICR_START (1 << 0) /* start bit */
+#define ICR_STOP (1 << 1) /* stop bit */
+#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */
+#define ICR_TB (1 << 3) /* transfer byte bit */
+#define ICR_MA (1 << 4) /* master abort */
+#define ICR_SCLE (1 << 5) /* master clock enable */
+#define ICR_IUE (1 << 6) /* unit enable */
+#define ICR_GCD (1 << 7) /* general call disable */
+#define ICR_ITEIE (1 << 8) /* enable tx interrupts */
+#define ICR_IRFIE (1 << 9) /* enable rx interrupts */
+#define ICR_BEIE (1 << 10) /* enable bus error ints */
+#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */
+#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */
+#define ICR_SADIE (1 << 13) /* slave address detected int enable */
+#define ICR_UR (1 << 14) /* unit reset */
+#define ICR_FM (1 << 15) /* fast mode */
+
+#define ISR_RWM (1 << 0) /* read/write mode */
+#define ISR_ACKNAK (1 << 1) /* ack/nak status */
+#define ISR_UB (1 << 2) /* unit busy */
+#define ISR_IBB (1 << 3) /* bus busy */
+#define ISR_SSD (1 << 4) /* slave stop detected */
+#define ISR_ALD (1 << 5) /* arbitration loss detected */
+#define ISR_ITE (1 << 6) /* tx buffer empty */
+#define ISR_IRF (1 << 7) /* rx buffer full */
+#define ISR_GCAD (1 << 8) /* general call address detected */
+#define ISR_SAD (1 << 9) /* slave address detected */
+#define ISR_BED (1 << 10) /* bus error no ACK/NAK */
struct pxa_i2c {
spinlock_t lock;
unsigned int slave_addr;
struct i2c_adapter adap;
+ struct clk *clk;
#ifdef CONFIG_I2C_PXA_SLAVE
struct i2c_slave_client *slave;
#endif
u32 icrlog[32];
void __iomem *reg_base;
+ unsigned int reg_shift;
unsigned long iobase;
unsigned long iosize;
int irq;
+ unsigned int use_pio :1;
+ unsigned int fast_mode :1;
};
-#define _IBMR(i2c) ((i2c)->reg_base + 0)
-#define _IDBR(i2c) ((i2c)->reg_base + 8)
-#define _ICR(i2c) ((i2c)->reg_base + 0x10)
-#define _ISR(i2c) ((i2c)->reg_base + 0x18)
-#define _ISAR(i2c) ((i2c)->reg_base + 0x20)
+#define _IBMR(i2c) ((i2c)->reg_base + (0x0 << (i2c)->reg_shift))
+#define _IDBR(i2c) ((i2c)->reg_base + (0x4 << (i2c)->reg_shift))
+#define _ICR(i2c) ((i2c)->reg_base + (0x8 << (i2c)->reg_shift))
+#define _ISR(i2c) ((i2c)->reg_base + (0xc << (i2c)->reg_shift))
+#define _ISAR(i2c) ((i2c)->reg_base + (0x10 << (i2c)->reg_shift))
/*
* I2C Slave mode address
const char *set;
const char *unset;
};
-#define BIT(m, s, u) { .mask = m, .set = s, .unset = u }
+#define PXA_BIT(m, s, u) { .mask = m, .set = s, .unset = u }
static inline void
decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
}
static const struct bits isr_bits[] = {
- BIT(ISR_RWM, "RX", "TX"),
- BIT(ISR_ACKNAK, "NAK", "ACK"),
- BIT(ISR_UB, "Bsy", "Rdy"),
- BIT(ISR_IBB, "BusBsy", "BusRdy"),
- BIT(ISR_SSD, "SlaveStop", NULL),
- BIT(ISR_ALD, "ALD", NULL),
- BIT(ISR_ITE, "TxEmpty", NULL),
- BIT(ISR_IRF, "RxFull", NULL),
- BIT(ISR_GCAD, "GenCall", NULL),
- BIT(ISR_SAD, "SlaveAddr", NULL),
- BIT(ISR_BED, "BusErr", NULL),
+ PXA_BIT(ISR_RWM, "RX", "TX"),
+ PXA_BIT(ISR_ACKNAK, "NAK", "ACK"),
+ PXA_BIT(ISR_UB, "Bsy", "Rdy"),
+ PXA_BIT(ISR_IBB, "BusBsy", "BusRdy"),
+ PXA_BIT(ISR_SSD, "SlaveStop", NULL),
+ PXA_BIT(ISR_ALD, "ALD", NULL),
+ PXA_BIT(ISR_ITE, "TxEmpty", NULL),
+ PXA_BIT(ISR_IRF, "RxFull", NULL),
+ PXA_BIT(ISR_GCAD, "GenCall", NULL),
+ PXA_BIT(ISR_SAD, "SlaveAddr", NULL),
+ PXA_BIT(ISR_BED, "BusErr", NULL),
};
static void decode_ISR(unsigned int val)
}
static const struct bits icr_bits[] = {
- BIT(ICR_START, "START", NULL),
- BIT(ICR_STOP, "STOP", NULL),
- BIT(ICR_ACKNAK, "ACKNAK", NULL),
- BIT(ICR_TB, "TB", NULL),
- BIT(ICR_MA, "MA", NULL),
- BIT(ICR_SCLE, "SCLE", "scle"),
- BIT(ICR_IUE, "IUE", "iue"),
- BIT(ICR_GCD, "GCD", NULL),
- BIT(ICR_ITEIE, "ITEIE", NULL),
- BIT(ICR_IRFIE, "IRFIE", NULL),
- BIT(ICR_BEIE, "BEIE", NULL),
- BIT(ICR_SSDIE, "SSDIE", NULL),
- BIT(ICR_ALDIE, "ALDIE", NULL),
- BIT(ICR_SADIE, "SADIE", NULL),
- BIT(ICR_UR, "UR", "ur"),
+ PXA_BIT(ICR_START, "START", NULL),
+ PXA_BIT(ICR_STOP, "STOP", NULL),
+ PXA_BIT(ICR_ACKNAK, "ACKNAK", NULL),
+ PXA_BIT(ICR_TB, "TB", NULL),
+ PXA_BIT(ICR_MA, "MA", NULL),
+ PXA_BIT(ICR_SCLE, "SCLE", "scle"),
+ PXA_BIT(ICR_IUE, "IUE", "iue"),
+ PXA_BIT(ICR_GCD, "GCD", NULL),
+ PXA_BIT(ICR_ITEIE, "ITEIE", NULL),
+ PXA_BIT(ICR_IRFIE, "IRFIE", NULL),
+ PXA_BIT(ICR_BEIE, "BEIE", NULL),
+ PXA_BIT(ICR_SSDIE, "SSDIE", NULL),
+ PXA_BIT(ICR_ALDIE, "ALDIE", NULL),
+ PXA_BIT(ICR_SADIE, "SADIE", NULL),
+ PXA_BIT(ICR_UR, "UR", "ur"),
};
+#ifdef CONFIG_I2C_PXA_SLAVE
static void decode_ICR(unsigned int val)
{
decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
printk("\n");
}
+#endif
static unsigned int i2c_debug = DEBUG;
readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
}
-#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __FUNCTION__)
+#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
#else
#define i2c_debug 0
#define eedbg(lvl, x...) do { if ((lvl) < 1) { printk(KERN_DEBUG "" x); } } while(0)
static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
+static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
{
unsigned int i;
- printk("i2c: error: %s\n", why);
- printk("i2c: msg_num: %d msg_idx: %d msg_ptr: %d\n",
+ printk(KERN_ERR "i2c: error: %s\n", why);
+ printk(KERN_ERR "i2c: msg_num: %d msg_idx: %d msg_ptr: %d\n",
i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
- printk("i2c: ICR: %08x ISR: %08x\n"
- "i2c: log: ", readl(_ICR(i2c)), readl(_ISR(i2c)));
+ printk(KERN_ERR "i2c: ICR: %08x ISR: %08x\n",
+ readl(_ICR(i2c)), readl(_ISR(i2c)));
+ printk(KERN_DEBUG "i2c: log: ");
for (i = 0; i < i2c->irqlogidx; i++)
printk("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
printk("\n");
static void i2c_pxa_abort(struct pxa_i2c *i2c)
{
- unsigned long timeout = jiffies + HZ/4;
+ int i = 250;
if (i2c_pxa_is_slavemode(i2c)) {
dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
return;
}
- while (time_before(jiffies, timeout) && (readl(_IBMR(i2c)) & 0x1) == 0) {
+ while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
unsigned long icr = readl(_ICR(i2c));
icr &= ~ICR_START;
show_state(i2c);
- msleep(1);
+ mdelay(1);
+ i --;
}
writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
show_state(i2c);
}
- if (timeout <= 0)
+ if (timeout < 0)
show_state(i2c);
- return timeout <= 0 ? I2C_RETRY : 0;
+ return timeout < 0 ? I2C_RETRY : 0;
}
static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
writel(i2c->slave_addr, _ISAR(i2c));
/* set control register values */
- writel(I2C_ICR_INIT, _ICR(i2c));
+ writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
#ifdef CONFIG_I2C_PXA_SLAVE
dev_info(&i2c->adap.dev, "Enabling slave mode\n");
writel(icr, _ICR(i2c));
}
+static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
+{
+ /* make timeout the same as for interrupt based functions */
+ long timeout = 2 * DEF_TIMEOUT;
+
+ /*
+ * Wait for the bus to become free.
+ */
+ while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
+ udelay(1000);
+ show_state(i2c);
+ }
+
+ if (timeout < 0) {
+ show_state(i2c);
+ dev_err(&i2c->adap.dev,
+ "i2c_pxa: timeout waiting for bus free\n");
+ return I2C_RETRY;
+ }
+
+ /*
+ * Set master mode.
+ */
+ writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
+
+ return 0;
+}
+
+static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
+ struct i2c_msg *msg, int num)
+{
+ unsigned long timeout = 500000; /* 5 seconds */
+ int ret = 0;
+
+ ret = i2c_pxa_pio_set_master(i2c);
+ if (ret)
+ goto out;
+
+ i2c->msg = msg;
+ i2c->msg_num = num;
+ i2c->msg_idx = 0;
+ i2c->msg_ptr = 0;
+ i2c->irqlogidx = 0;
+
+ i2c_pxa_start_message(i2c);
+
+ while (i2c->msg_num > 0 && --timeout) {
+ i2c_pxa_handler(0, i2c);
+ udelay(10);
+ }
+
+ i2c_pxa_stop_message(i2c);
+
+ /*
+ * We place the return code in i2c->msg_idx.
+ */
+ ret = i2c->msg_idx;
+
+out:
+ if (timeout == 0)
+ i2c_pxa_scream_blue_murder(i2c, "timeout");
+
+ return ret;
+}
+
/*
* We are protected by the adapter bus mutex.
*/
return ret;
}
+static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
+ struct i2c_msg msgs[], int num)
+{
+ struct pxa_i2c *i2c = adap->algo_data;
+ int ret, i;
+
+ /* If the I2C controller is disabled we need to reset it
+ (probably due to a suspend/resume destroying state). We do
+ this here as we can then avoid worrying about resuming the
+ controller before its users. */
+ if (!(readl(_ICR(i2c)) & ICR_IUE))
+ i2c_pxa_reset(i2c);
+
+ for (i = adap->retries; i >= 0; i--) {
+ ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
+ if (ret != I2C_RETRY)
+ goto out;
+
+ if (i2c_debug)
+ dev_dbg(&adap->dev, "Retrying transmission\n");
+ udelay(100);
+ }
+ i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
+ ret = -EREMOTEIO;
+ out:
+ i2c_pxa_set_slave(i2c, ret);
+ return ret;
+}
+
/*
* i2c_pxa_master_complete - complete the message and wake up.
*/
i2c->msg_num = 0;
if (ret)
i2c->msg_idx = ret;
- wake_up(&i2c->wait);
+ if (!i2c->use_pio)
+ wake_up(&i2c->wait);
}
static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
struct pxa_i2c *i2c = adap->algo_data;
int ret, i;
- /* If the I2C controller is disabled we need to reset it (probably due
- to a suspend/resume destroying state). We do this here as we can then
- avoid worrying about resuming the controller before its users. */
- if (!(readl(_ICR(i2c)) & ICR_IUE))
- i2c_pxa_reset(i2c);
-
for (i = adap->retries; i >= 0; i--) {
ret = i2c_pxa_do_xfer(i2c, msgs, num);
if (ret != I2C_RETRY)
.functionality = i2c_pxa_functionality,
};
-#define res_len(r) ((r)->end - (r)->start + 1)
+static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
+ .master_xfer = i2c_pxa_pio_xfer,
+ .functionality = i2c_pxa_functionality,
+};
+
static int i2c_pxa_probe(struct platform_device *dev)
{
struct pxa_i2c *i2c;
struct resource *res;
struct i2c_pxa_platform_data *plat = dev->dev.platform_data;
+ struct platform_device_id *id = platform_get_device_id(dev);
int ret;
int irq;
if (res == NULL || irq < 0)
return -ENODEV;
- if (!request_mem_region(res->start, res_len(res), res->name))
+ if (!request_mem_region(res->start, resource_size(res), res->name))
return -ENOMEM;
i2c = kzalloc(sizeof(struct pxa_i2c), GFP_KERNEL);
}
i2c->adap.owner = THIS_MODULE;
- i2c->adap.algo = &i2c_pxa_algorithm;
i2c->adap.retries = 5;
spin_lock_init(&i2c->lock);
init_waitqueue_head(&i2c->wait);
- sprintf(i2c->adap.name, "pxa_i2c-i2c.%u", dev->id);
+ /*
+ * If "dev->id" is negative we consider it as zero.
+ * The reason to do so is to avoid sysfs names that only make
+ * sense when there are multiple adapters.
+ */
+ i2c->adap.nr = dev->id != -1 ? dev->id : 0;
+ snprintf(i2c->adap.name, sizeof(i2c->adap.name), "pxa_i2c-i2c.%u",
+ i2c->adap.nr);
- i2c->reg_base = ioremap(res->start, res_len(res));
+ i2c->clk = clk_get(&dev->dev, 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_shift = REG_SHIFT(id->driver_data);
i2c->iobase = res->start;
- i2c->iosize = res_len(res);
+ i2c->iosize = resource_size(res);
i2c->irq = irq;
}
#endif
- switch (dev->id) {
- case 0:
-#ifdef CONFIG_PXA27x
- pxa_gpio_mode(GPIO117_I2CSCL_MD);
- pxa_gpio_mode(GPIO118_I2CSDA_MD);
-#endif
- pxa_set_cken(CKEN_I2C, 1);
- break;
-#ifdef CONFIG_PXA27x
- case 1:
- local_irq_disable();
- PCFR |= PCFR_PI2CEN;
- local_irq_enable();
- pxa_set_cken(CKEN_PWRI2C, 1);
-#endif
- }
+ clk_enable(i2c->clk);
- ret = request_irq(irq, i2c_pxa_handler, IRQF_DISABLED,
- i2c->adap.name, i2c);
- if (ret)
- goto ereqirq;
+ if (plat) {
+ i2c->adap.class = plat->class;
+ i2c->use_pio = plat->use_pio;
+ i2c->fast_mode = plat->fast_mode;
+ }
+ 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_DISABLED,
+ i2c->adap.name, i2c);
+ if (ret)
+ goto ereqirq;
+ }
i2c_pxa_reset(i2c);
i2c->adap.algo_data = i2c;
i2c->adap.dev.parent = &dev->dev;
- if (plat) {
- i2c->adap.class = plat->class;
- }
-
- /*
- * If "dev->id" is negative we consider it as zero.
- * The reason to do so is to avoid sysfs names that only make
- * sense when there are multiple adapters.
- */
- i2c->adap.nr = dev->id != -1 ? dev->id : 0;
-
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0) {
printk(KERN_INFO "I2C: Failed to add bus\n");
#ifdef CONFIG_I2C_PXA_SLAVE
printk(KERN_INFO "I2C: %s: PXA I2C adapter, slave address %d\n",
- i2c->adap.dev.bus_id, i2c->slave_addr);
+ dev_name(&i2c->adap.dev), i2c->slave_addr);
#else
printk(KERN_INFO "I2C: %s: PXA I2C adapter\n",
- i2c->adap.dev.bus_id);
+ dev_name(&i2c->adap.dev));
#endif
return 0;
eadapt:
- free_irq(irq, i2c);
+ if (!i2c->use_pio)
+ free_irq(irq, i2c);
ereqirq:
- switch (dev->id) {
- case 0:
- pxa_set_cken(CKEN_I2C, 0);
- break;
-#ifdef CONFIG_PXA27x
- case 1:
- pxa_set_cken(CKEN_PWRI2C, 0);
- local_irq_disable();
- PCFR &= ~PCFR_PI2CEN;
- local_irq_enable();
-#endif
- }
+ clk_disable(i2c->clk);
+ iounmap(i2c->reg_base);
eremap:
+ clk_put(i2c->clk);
+eclk:
kfree(i2c);
emalloc:
- release_mem_region(res->start, res_len(res));
+ release_mem_region(res->start, resource_size(res));
return ret;
}
-static int i2c_pxa_remove(struct platform_device *dev)
+static int __exit i2c_pxa_remove(struct platform_device *dev)
{
struct pxa_i2c *i2c = platform_get_drvdata(dev);
platform_set_drvdata(dev, NULL);
i2c_del_adapter(&i2c->adap);
- free_irq(i2c->irq, i2c);
- switch (dev->id) {
- case 0:
- pxa_set_cken(CKEN_I2C, 0);
- break;
-#ifdef CONFIG_PXA27x
- case 1:
- pxa_set_cken(CKEN_PWRI2C, 0);
- local_irq_disable();
- PCFR &= ~PCFR_PI2CEN;
- local_irq_enable();
-#endif
- }
+ if (!i2c->use_pio)
+ free_irq(i2c->irq, i2c);
+
+ clk_disable(i2c->clk);
+ clk_put(i2c->clk);
+
+ iounmap(i2c->reg_base);
release_mem_region(i2c->iobase, i2c->iosize);
kfree(i2c);
return 0;
}
+#ifdef CONFIG_PM
+static int i2c_pxa_suspend_noirq(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct pxa_i2c *i2c = platform_get_drvdata(pdev);
+
+ clk_disable(i2c->clk);
+
+ return 0;
+}
+
+static int i2c_pxa_resume_noirq(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct pxa_i2c *i2c = platform_get_drvdata(pdev);
+
+ clk_enable(i2c->clk);
+ i2c_pxa_reset(i2c);
+
+ return 0;
+}
+
+static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
+ .suspend_noirq = i2c_pxa_suspend_noirq,
+ .resume_noirq = i2c_pxa_resume_noirq,
+};
+
+#define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
+#else
+#define I2C_PXA_DEV_PM_OPS NULL
+#endif
+
static struct platform_driver i2c_pxa_driver = {
.probe = i2c_pxa_probe,
- .remove = i2c_pxa_remove,
+ .remove = __exit_p(i2c_pxa_remove),
.driver = {
.name = "pxa2xx-i2c",
+ .owner = THIS_MODULE,
+ .pm = I2C_PXA_DEV_PM_OPS,
},
+ .id_table = i2c_pxa_id_table,
};
static int __init i2c_adap_pxa_init(void)
return platform_driver_register(&i2c_pxa_driver);
}
-static void i2c_adap_pxa_exit(void)
+static void __exit i2c_adap_pxa_exit(void)
{
- return platform_driver_unregister(&i2c_pxa_driver);
+ platform_driver_unregister(&i2c_pxa_driver);
}
MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pxa2xx-i2c");
-module_init(i2c_adap_pxa_init);
+subsys_initcall(i2c_adap_pxa_init);
module_exit(i2c_adap_pxa_exit);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff