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path: root/drivers/i2c/busses/i2c-pxa.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-pxa.c')
-rw-r--r--drivers/i2c/busses/i2c-pxa.c281
1 files changed, 219 insertions, 62 deletions
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index f4c19a97e0b..be671f7a0e0 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -29,38 +29,69 @@
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/i2c-pxa.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/io.h>
+#include <linux/i2c/pxa-i2c.h>
#include <asm/irq.h>
-#include <plat/i2c.h>
+
+struct pxa_reg_layout {
+ u32 ibmr;
+ u32 idbr;
+ u32 icr;
+ u32 isr;
+ u32 isar;
+};
+
+enum pxa_i2c_types {
+ REGS_PXA2XX,
+ REGS_PXA3XX,
+ REGS_CE4100,
+};
/*
- * I2C register offsets will be shifted 0 or 1 bit left, depending on
- * different SoCs
+ * I2C registers definitions
*/
-#define REG_SHIFT_0 (0 << 0)
-#define REG_SHIFT_1 (1 << 0)
-#define REG_SHIFT(d) ((d) & 0x1)
+static struct pxa_reg_layout pxa_reg_layout[] = {
+ [REGS_PXA2XX] = {
+ .ibmr = 0x00,
+ .idbr = 0x08,
+ .icr = 0x10,
+ .isr = 0x18,
+ .isar = 0x20,
+ },
+ [REGS_PXA3XX] = {
+ .ibmr = 0x00,
+ .idbr = 0x04,
+ .icr = 0x08,
+ .isr = 0x0c,
+ .isar = 0x10,
+ },
+ [REGS_CE4100] = {
+ .ibmr = 0x14,
+ .idbr = 0x0c,
+ .icr = 0x00,
+ .isr = 0x04,
+ /* no isar register */
+ },
+};
static const struct platform_device_id i2c_pxa_id_table[] = {
- { "pxa2xx-i2c", REG_SHIFT_1 },
- { "pxa3xx-pwri2c", REG_SHIFT_0 },
+ { "pxa2xx-i2c", REGS_PXA2XX },
+ { "pxa3xx-pwri2c", REGS_PXA3XX },
+ { "ce4100-i2c", REGS_CE4100 },
{ },
};
MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
/*
- * I2C registers and bit definitions
+ * I2C 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 */
@@ -78,6 +109,8 @@ MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
#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 ICR_HS (1 << 16) /* High Speed mode */
+#define ICR_GPIOEN (1 << 19) /* enable GPIO mode for SCL in HS */
#define ISR_RWM (1 << 0) /* read/write mode */
#define ISR_ACKNAK (1 << 1) /* ack/nak status */
@@ -111,7 +144,11 @@ struct pxa_i2c {
u32 icrlog[32];
void __iomem *reg_base;
- unsigned int reg_shift;
+ void __iomem *reg_ibmr;
+ void __iomem *reg_idbr;
+ void __iomem *reg_icr;
+ void __iomem *reg_isr;
+ void __iomem *reg_isar;
unsigned long iobase;
unsigned long iosize;
@@ -119,13 +156,17 @@ struct pxa_i2c {
int irq;
unsigned int use_pio :1;
unsigned int fast_mode :1;
+ unsigned int high_mode:1;
+ unsigned char master_code;
+ unsigned long rate;
+ bool highmode_enter;
};
-#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))
+#define _IBMR(i2c) ((i2c)->reg_ibmr)
+#define _IDBR(i2c) ((i2c)->reg_idbr)
+#define _ICR(i2c) ((i2c)->reg_icr)
+#define _ISR(i2c) ((i2c)->reg_isr)
+#define _ISAR(i2c) ((i2c)->reg_isar)
/*
* I2C Slave mode address
@@ -418,10 +459,12 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
writel(I2C_ISR_INIT, _ISR(i2c));
writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
- writel(i2c->slave_addr, _ISAR(i2c));
+ if (i2c->reg_isar)
+ writel(i2c->slave_addr, _ISAR(i2c));
/* set control register values */
writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
+ writel(readl(_ICR(i2c)) | (i2c->high_mode ? ICR_HS : 0), _ICR(i2c));
#ifdef CONFIG_I2C_PXA_SLAVE
dev_info(&i2c->adap.dev, "Enabling slave mode\n");
@@ -643,6 +686,34 @@ static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
return 0;
}
+/*
+ * PXA I2C send master code
+ * 1. Load master code to IDBR and send it.
+ * Note for HS mode, set ICR [GPIOEN].
+ * 2. Wait until win arbitration.
+ */
+static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
+{
+ u32 icr;
+ long timeout;
+
+ spin_lock_irq(&i2c->lock);
+ i2c->highmode_enter = true;
+ writel(i2c->master_code, _IDBR(i2c));
+
+ icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
+ icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
+ writel(icr, _ICR(i2c));
+
+ spin_unlock_irq(&i2c->lock);
+ timeout = wait_event_timeout(i2c->wait,
+ i2c->highmode_enter == false, HZ * 1);
+
+ i2c->highmode_enter = false;
+
+ return (timeout == 0) ? I2C_RETRY : 0;
+}
+
static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
struct i2c_msg *msg, int num)
{
@@ -706,6 +777,14 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
goto out;
}
+ if (i2c->high_mode) {
+ ret = i2c_pxa_send_mastercode(i2c);
+ if (ret) {
+ dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
+ goto out;
+ }
+ }
+
spin_lock_irq(&i2c->lock);
i2c->msg = msg;
@@ -729,8 +808,10 @@ static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
*/
ret = i2c->msg_idx;
- if (timeout == 0)
+ if (!timeout && i2c->msg_num) {
i2c_pxa_scream_blue_murder(i2c, "timeout");
+ ret = I2C_RETRY;
+ }
out:
return ret;
@@ -915,11 +996,16 @@ static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
writel(icr, _ICR(i2c));
}
+#define VALID_INT_SOURCE (ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
+ ISR_SAD | ISR_BED)
static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
{
struct pxa_i2c *i2c = dev_id;
u32 isr = readl(_ISR(i2c));
+ if (!(isr & VALID_INT_SOURCE))
+ return IRQ_NONE;
+
if (i2c_debug > 2 && 0) {
dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
__func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
@@ -934,7 +1020,7 @@ static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
/*
* Always clear all pending IRQs.
*/
- writel(isr & (ISR_SSD|ISR_ALD|ISR_ITE|ISR_IRF|ISR_SAD|ISR_BED), _ISR(i2c));
+ writel(isr & VALID_INT_SOURCE, _ISR(i2c));
if (isr & ISR_SAD)
i2c_pxa_slave_start(i2c, isr);
@@ -946,11 +1032,14 @@ static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
i2c_pxa_slave_txempty(i2c, isr);
if (isr & ISR_IRF)
i2c_pxa_slave_rxfull(i2c, isr);
- } else if (i2c->msg) {
+ } else if (i2c->msg && (!i2c->highmode_enter)) {
if (isr & ISR_ITE)
i2c_pxa_irq_txempty(i2c, isr);
if (isr & ISR_IRF)
i2c_pxa_irq_rxfull(i2c, isr);
+ } else if ((isr & ISR_ITE) && i2c->highmode_enter) {
+ i2c->highmode_enter = false;
+ wake_up(&i2c->wait);
} else {
i2c_pxa_scream_blue_murder(i2c, "spurious irq");
}
@@ -995,22 +1084,62 @@ static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
.functionality = i2c_pxa_functionality,
};
-static int i2c_pxa_probe(struct platform_device *dev)
+static const struct of_device_id i2c_pxa_dt_ids[] = {
+ { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
+ { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
+ { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA2XX },
+ {}
+};
+MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
+
+static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
+ enum pxa_i2c_types *i2c_types)
{
- struct pxa_i2c *i2c;
- struct resource *res;
- struct i2c_pxa_platform_data *plat = dev->dev.platform_data;
- const struct platform_device_id *id = platform_get_device_id(dev);
- int ret;
- int irq;
+ struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *of_id =
+ of_match_device(i2c_pxa_dt_ids, &pdev->dev);
- res = platform_get_resource(dev, IORESOURCE_MEM, 0);
- irq = platform_get_irq(dev, 0);
- if (res == NULL || irq < 0)
- return -ENODEV;
+ if (!of_id)
+ return 1;
+
+ /* For device tree we always use the dynamic or alias-assigned ID */
+ i2c->adap.nr = -1;
+
+ if (of_get_property(np, "mrvl,i2c-polling", NULL))
+ i2c->use_pio = 1;
+ if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
+ i2c->fast_mode = 1;
+ *i2c_types = (u32)(of_id->data);
+ return 0;
+}
- if (!request_mem_region(res->start, resource_size(res), res->name))
- return -ENOMEM;
+static int i2c_pxa_probe_pdata(struct platform_device *pdev,
+ struct pxa_i2c *i2c,
+ enum pxa_i2c_types *i2c_types)
+{
+ struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
+ const struct platform_device_id *id = platform_get_device_id(pdev);
+
+ *i2c_types = id->driver_data;
+ if (plat) {
+ i2c->use_pio = plat->use_pio;
+ i2c->fast_mode = plat->fast_mode;
+ i2c->high_mode = plat->high_mode;
+ i2c->master_code = plat->master_code;
+ if (!i2c->master_code)
+ i2c->master_code = 0xe;
+ i2c->rate = plat->rate;
+ }
+ return 0;
+}
+
+static int i2c_pxa_probe(struct platform_device *dev)
+{
+ struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
+ enum pxa_i2c_types i2c_type;
+ struct pxa_i2c *i2c;
+ struct resource *res = NULL;
+ int ret, irq;
i2c = kzalloc(sizeof(struct pxa_i2c), GFP_KERNEL);
if (!i2c) {
@@ -1018,20 +1147,34 @@ static int i2c_pxa_probe(struct platform_device *dev)
goto emalloc;
}
+ /* Default adapter num to device id; i2c_pxa_probe_dt can override. */
+ i2c->adap.nr = dev->id;
+
+ ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
+ if (ret > 0)
+ ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
+ if (ret < 0)
+ goto eclk;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ irq = platform_get_irq(dev, 0);
+ if (res == NULL || irq < 0) {
+ ret = -ENODEV;
+ goto eclk;
+ }
+
+ if (!request_mem_region(res->start, resource_size(res), res->name)) {
+ ret = -ENOMEM;
+ goto eclk;
+ }
+
i2c->adap.owner = THIS_MODULE;
i2c->adap.retries = 5;
spin_lock_init(&i2c->lock);
init_waitqueue_head(&i2c->wait);
- /*
- * 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);
+ strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
i2c->clk = clk_get(&dev->dev, NULL);
if (IS_ERR(i2c->clk)) {
@@ -1044,7 +1187,13 @@ static int i2c_pxa_probe(struct platform_device *dev)
ret = -EIO;
goto eremap;
}
- i2c->reg_shift = REG_SHIFT(id->driver_data);
+
+ 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);
@@ -1052,28 +1201,34 @@ static int i2c_pxa_probe(struct platform_device *dev)
i2c->irq = irq;
i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
+ i2c->highmode_enter = false;
-#ifdef CONFIG_I2C_PXA_SLAVE
if (plat) {
+#ifdef CONFIG_I2C_PXA_SLAVE
i2c->slave_addr = plat->slave_addr;
i2c->slave = plat->slave;
- }
#endif
-
- clk_enable(i2c->clk);
-
- if (plat) {
i2c->adap.class = plat->class;
- i2c->use_pio = plat->use_pio;
- i2c->fast_mode = plat->fast_mode;
}
+ if (i2c->high_mode) {
+ if (i2c->rate) {
+ clk_set_rate(i2c->clk, i2c->rate);
+ pr_info("i2c: <%s> set rate to %ld\n",
+ i2c->adap.name, clk_get_rate(i2c->clk));
+ } else
+ pr_warn("i2c: <%s> clock rate not set\n",
+ i2c->adap.name);
+ }
+
+ clk_prepare_enable(i2c->clk);
+
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);
+ ret = request_irq(irq, i2c_pxa_handler, IRQF_SHARED,
+ dev_name(&dev->dev), i2c);
if (ret)
goto ereqirq;
}
@@ -1082,6 +1237,9 @@ static int i2c_pxa_probe(struct platform_device *dev)
i2c->adap.algo_data = i2c;
i2c->adap.dev.parent = &dev->dev;
+#ifdef CONFIG_OF
+ i2c->adap.dev.of_node = dev->dev.of_node;
+#endif
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0) {
@@ -1104,7 +1262,7 @@ eadapt:
if (!i2c->use_pio)
free_irq(irq, i2c);
ereqirq:
- clk_disable(i2c->clk);
+ clk_disable_unprepare(i2c->clk);
iounmap(i2c->reg_base);
eremap:
clk_put(i2c->clk);
@@ -1115,17 +1273,15 @@ emalloc:
return ret;
}
-static int __exit i2c_pxa_remove(struct platform_device *dev)
+static int 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);
if (!i2c->use_pio)
free_irq(i2c->irq, i2c);
- clk_disable(i2c->clk);
+ clk_disable_unprepare(i2c->clk);
clk_put(i2c->clk);
iounmap(i2c->reg_base);
@@ -1169,11 +1325,12 @@ static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
static struct platform_driver i2c_pxa_driver = {
.probe = i2c_pxa_probe,
- .remove = __exit_p(i2c_pxa_remove),
+ .remove = i2c_pxa_remove,
.driver = {
.name = "pxa2xx-i2c",
.owner = THIS_MODULE,
.pm = I2C_PXA_DEV_PM_OPS,
+ .of_match_table = i2c_pxa_dt_ids,
},
.id_table = i2c_pxa_id_table,
};
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-05 17:49:51 +0000