[PATCHv4 2/9] i2c: mv64xxx: make the registers offset configurable

Maxime Ripard
2013-06-12T08:07:11Z

The Allwinner i2c controller uses the same logic as the Marvell one, but
with slightly different register offsets.

Introduce a structure that will be passed by either the pdata or
associated to the compatible strings, and that holds the various
registers that might be needed.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
drivers/i2c/busses/i2c-mv64xxx.c | 81 +++++++++++++++++++++-------------------
include/linux/mv643xx_i2c.h | 27 ++++++++++++--
2 files changed, 66 insertions(+), 42 deletions(-)

diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index d70a2fda..f9e076e 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -19,20 +19,12 @@
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_i2c.h>
#include <linux/clk.h>
#include <linux/err.h>

-/* Register defines */
-#define MV64XXX_I2C_REG_SLAVE_ADDR 0x00
-#define MV64XXX_I2C_REG_DATA 0x04
-#define MV64XXX_I2C_REG_CONTROL 0x08
-#define MV64XXX_I2C_REG_STATUS 0x0c
-#define MV64XXX_I2C_REG_BAUD 0x0c
-#define MV64XXX_I2C_REG_EXT_SLAVE_ADDR 0x10
-#define MV64XXX_I2C_REG_SOFT_RESET 0x1c
-
#define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1)
#define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7)
#define MV64XXX_I2C_BAUD_DIV_M(val) ((val & 0xf) << 3)
@@ -98,6 +90,7 @@ struct mv64xxx_i2c_data {
u32 aborting;
u32 cntl_bits;
void __iomem *reg_base;
+ struct mv64xxx_i2c_regs *regs;
u32 addr1;
u32 addr2;
u32 bytes_left;
@@ -154,13 +147,13 @@ mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
static void
mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data)
{
- writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SOFT_RESET);
+ writel(0, drv_data->reg_base + drv_data->regs->soft_reset);
writel(MV64XXX_I2C_BAUD_DIV_M(drv_data->freq_m) | MV64XXX_I2C_BAUD_DIV_N(drv_data->freq_n),
- drv_data->reg_base + MV64XXX_I2C_REG_BAUD);
- writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SLAVE_ADDR);
- writel(0, drv_data->reg_base + MV64XXX_I2C_REG_EXT_SLAVE_ADDR);
+ drv_data->reg_base + drv_data->regs->clock);
+ writel(0, drv_data->reg_base + drv_data->regs->addr);
+ writel(0, drv_data->reg_base + drv_data->regs->ext_addr);
writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
drv_data->state = MV64XXX_I2C_STATE_IDLE;
}

@@ -282,7 +275,7 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)

drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START;
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);

drv_data->msgs++;
drv_data->num_msgs--;
@@ -300,48 +293,48 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)

case MV64XXX_I2C_ACTION_CONTINUE:
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_SEND_START:
writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_SEND_ADDR_1:
writel(drv_data->addr1,
- drv_data->reg_base + MV64XXX_I2C_REG_DATA);
+ drv_data->reg_base + drv_data->regs->data);
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_SEND_ADDR_2:
writel(drv_data->addr2,
- drv_data->reg_base + MV64XXX_I2C_REG_DATA);
+ drv_data->reg_base + drv_data->regs->data);
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_SEND_DATA:
writel(drv_data->msg->buf[drv_data->byte_posn++],
- drv_data->reg_base + MV64XXX_I2C_REG_DATA);
+ drv_data->reg_base + drv_data->regs->data);
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_RCV_DATA:
drv_data->msg->buf[drv_data->byte_posn++] =
- readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
+ readl(drv_data->reg_base + drv_data->regs->data);
writel(drv_data->cntl_bits,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
break;

case MV64XXX_I2C_ACTION_RCV_DATA_STOP:
drv_data->msg->buf[drv_data->byte_posn++] =
- readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
+ readl(drv_data->reg_base + drv_data->regs->data);
drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
drv_data->block = 0;
wake_up(&drv_data->waitq);
break;
@@ -356,7 +349,7 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
case MV64XXX_I2C_ACTION_SEND_STOP:
drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
- drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
+ drv_data->reg_base + drv_data->regs->control);
drv_data->block = 0;
wake_up(&drv_data->waitq);
break;
@@ -372,9 +365,9 @@ mv64xxx_i2c_intr(int irq, void *dev_id)
irqreturn_t rc = IRQ_NONE;

spin_lock_irqsave(&drv_data->lock, flags);
- while (readl(drv_data->reg_base + MV64XXX_I2C_REG_CONTROL) &
+ while (readl(drv_data->reg_base + drv_data->regs->control) &
MV64XXX_I2C_REG_CONTROL_IFLG) {
- status = readl(drv_data->reg_base + MV64XXX_I2C_REG_STATUS);
+ status = readl(drv_data->reg_base + drv_data->regs->status);
mv64xxx_i2c_fsm(drv_data, status);
mv64xxx_i2c_do_action(drv_data);
rc = IRQ_HANDLED;
@@ -496,6 +489,12 @@ static const struct i2c_algorithm mv64xxx_i2c_algo = {
*****************************************************************************
*/
#ifdef CONFIG_OF
+static const struct of_device_id mv64xxx_i2c_of_match_table[] = {
+ { .compatible = "marvell,mv64xxx-i2c", .data = &mv64xxx_i2c_regs_mv64xxx},
+ {}
+};
+MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table);
+
static int
mv64xxx_calc_freq(const int tclk, const int n, const int m)
{
@@ -528,8 +527,10 @@ mv64xxx_find_baud_factors(const u32 req_freq, const u32 tclk, u32 *best_n,

static int
mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
- struct device_node *np)
+ struct device *dev)
{
+ const struct of_device_id *device;
+ struct device_node *np = dev->of_node;
u32 bus_freq, tclk;
int rc = 0;

@@ -558,6 +559,13 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
* So hard code the value to 1 second.
*/
drv_data->adapter.timeout = HZ;
+
+ device = of_match_device(mv64xxx_i2c_of_match_table, dev);
+ if (!device)
+ return -ENODEV;
+
+ drv_data->regs = (struct mv64xxx_i2c_regs *)device->data;
+
out:
return rc;
#endif
@@ -565,7 +573,7 @@ out:
#else /* CONFIG_OF */
static int
mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
- struct device_node *np)
+ struct device *dev)
{
return -ENODEV;
}
@@ -611,8 +619,9 @@ mv64xxx_i2c_probe(struct platform_device *pd)
drv_data->freq_n = pdata->freq_n;
drv_data->irq = platform_get_irq(pd, 0);
drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout);
+ drv_data->regs = pdata->regs;
} else if (pd->dev.of_node) {
- rc = mv64xxx_of_config(drv_data, pd->dev.of_node);
+ rc = mv64xxx_of_config(drv_data, &pd->dev);
if (rc)
goto exit_clk;
}
@@ -680,12 +689,6 @@ mv64xxx_i2c_remove(struct platform_device *dev)
return 0;
}

-static const struct of_device_id mv64xxx_i2c_of_match_table[] = {
- { .compatible = "marvell,mv64xxx-i2c", },
- {}
-};
-MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table);
-
static struct platform_driver mv64xxx_i2c_driver = {
.probe = mv64xxx_i2c_probe,
.remove = mv64xxx_i2c_remove,
diff --git a/include/linux/mv643xx_i2c.h b/include/linux/mv643xx_i2c.h
index 5db5152..9304c94 100644
--- a/include/linux/mv643xx_i2c.h
+++ b/include/linux/mv643xx_i2c.h
@@ -12,11 +12,32 @@

#define MV64XXX_I2C_CTLR_NAME "mv64xxx_i2c"

+struct mv64xxx_i2c_regs {
+ u8 addr;
+ u8 ext_addr;
+ u8 data;
+ u8 control;
+ u8 status;
+ u8 clock;
+ u8 soft_reset;
+};
+
+struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = {
+ .addr = 0x00,
+ .ext_addr = 0x10,
+ .data = 0x04,
+ .control = 0x08,
+ .status = 0x0c,
+ .clock = 0x0c,
+ .soft_reset = 0x1c,
+};
+
/* i2c Platform Device, Driver Data */
struct mv64xxx_i2c_pdata {
- u32 freq_m;
- u32 freq_n;
- u32 timeout; /* In milliseconds */
+ u32 freq_m;
+ u32 freq_n;
+ struct mv64xxx_i2c_regs *regs;
+ u32 timeout; /* In milliseconds */
};

#endif /*_MV64XXX_I2C_H_*/
--
1.8.3