#include <linux/interrupt.h>
#include <linux/i2c-pxa.h>
#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.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 <asm/arch/pxa2xx-gpio.h>
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
unsigned long iosize;
int irq;
+ int use_pio;
};
#define _IBMR(i2c) ((i2c)->reg_base + 0)
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)
{
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 (timeout-- && i2c->msg_num > 0) {
+ 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)
.functionality = i2c_pxa_functionality,
};
+static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
+ .master_xfer = i2c_pxa_pio_xfer,
+ .functionality = i2c_pxa_functionality,
+};
+
+static void i2c_pxa_enable(struct platform_device *dev)
+{
+ if (cpu_is_pxa27x()) {
+ switch (dev->id) {
+ case 0:
+ pxa_gpio_mode(GPIO117_I2CSCL_MD);
+ pxa_gpio_mode(GPIO118_I2CSDA_MD);
+ break;
+ case 1:
+ local_irq_disable();
+ PCFR |= PCFR_PI2CEN;
+ local_irq_enable();
+ break;
+ }
+ }
+}
+
+static void i2c_pxa_disable(struct platform_device *dev)
+{
+ if (cpu_is_pxa27x() && dev->id == 1) {
+ local_irq_disable();
+ PCFR &= ~PCFR_PI2CEN;
+ local_irq_enable();
+ }
+}
+
#define res_len(r) ((r)->end - (r)->start + 1)
static int i2c_pxa_probe(struct platform_device *dev)
{
}
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->clk = clk_get(&dev->dev, "I2CCLK");
+ if (IS_ERR(i2c->clk)) {
+ ret = PTR_ERR(i2c->clk);
+ goto eclk;
+ }
i2c->reg_base = ioremap(res->start, res_len(res));
if (!i2c->reg_base) {
}
#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);
+ i2c_pxa_enable(dev);
- 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;
+ }
+ 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 >= 0 ? dev->id : 0;
-
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0) {
printk(KERN_INFO "I2C: Failed to add bus\n");
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);
+ i2c_pxa_disable(dev);
+ iounmap(i2c->reg_base);
eremap:
+ clk_put(i2c->clk);
+eclk:
kfree(i2c);
emalloc:
release_mem_region(res->start, res_len(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);
+ i2c_pxa_disable(dev);
+
+ iounmap(i2c->reg_base);
release_mem_region(i2c->iobase, i2c->iosize);
kfree(i2c);
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,
},
};
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);
module_exit(i2c_adap_pxa_exit);