[PATCHv5,2/8] i2c: mv64xxx: make the registers offset configurable
Andrew Lunn
andrew at lunn.ch
Fri Jun 14 15:36:53 EDT 2013
On Wed, Jun 12, 2013 at 06:53:31PM +0200, Maxime Ripard wrote:
> 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 at free-electrons.com>
Hi Maxime
I tested on a Kirkwood QNAP. It has an RTC on the i2c bus. It still
gives the correct time with your patches applied.
Tested-by: Andrew Lunn <andrew at lunn.ch>
Andrew
>
> ---
> drivers/i2c/busses/i2c-mv64xxx.c | 101 ++++++++++++++++++++++++---------------
> 1 file changed, 62 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
> index d70a2fda..7ba9bac 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)
> @@ -89,6 +81,16 @@ enum {
> MV64XXX_I2C_ACTION_SEND_STOP,
> };
>
> +struct mv64xxx_i2c_regs {
> + u8 addr;
> + u8 ext_addr;
> + u8 data;
> + u8 control;
> + u8 status;
> + u8 clock;
> + u8 soft_reset;
> +};
> +
> struct mv64xxx_i2c_data {
> struct i2c_msg *msgs;
> int num_msgs;
> @@ -98,6 +100,7 @@ struct mv64xxx_i2c_data {
> u32 aborting;
> u32 cntl_bits;
> void __iomem *reg_base;
> + struct mv64xxx_i2c_regs reg_offsets;
> u32 addr1;
> u32 addr2;
> u32 bytes_left;
> @@ -116,6 +119,16 @@ struct mv64xxx_i2c_data {
> struct i2c_adapter adapter;
> };
>
> +static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = {
> + .addr = 0x00,
> + .ext_addr = 0x10,
> + .data = 0x04,
> + .control = 0x08,
> + .status = 0x0c,
> + .clock = 0x0c,
> + .soft_reset = 0x1c,
> +};
> +
> static void
> mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
> struct i2c_msg *msg)
> @@ -154,13 +167,13 @@ 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->reg_offsets.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->reg_offsets.clock);
> + writel(0, drv_data->reg_base + drv_data->reg_offsets.addr);
> + writel(0, drv_data->reg_base + drv_data->reg_offsets.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->reg_offsets.control);
> drv_data->state = MV64XXX_I2C_STATE_IDLE;
> }
>
> @@ -282,7 +295,7 @@ 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->reg_offsets.control);
>
> drv_data->msgs++;
> drv_data->num_msgs--;
> @@ -300,48 +313,48 @@ 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->reg_offsets.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->reg_offsets.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->reg_offsets.data);
> writel(drv_data->cntl_bits,
> - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
> + drv_data->reg_base + drv_data->reg_offsets.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->reg_offsets.data);
> writel(drv_data->cntl_bits,
> - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
> + drv_data->reg_base + drv_data->reg_offsets.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->reg_offsets.data);
> writel(drv_data->cntl_bits,
> - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
> + drv_data->reg_base + drv_data->reg_offsets.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->reg_offsets.data);
> writel(drv_data->cntl_bits,
> - drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
> + drv_data->reg_base + drv_data->reg_offsets.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->reg_offsets.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->reg_offsets.control);
> drv_data->block = 0;
> wake_up(&drv_data->waitq);
> break;
> @@ -356,7 +369,7 @@ 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->reg_offsets.control);
> drv_data->block = 0;
> wake_up(&drv_data->waitq);
> break;
> @@ -372,9 +385,9 @@ 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->reg_offsets.control) &
> MV64XXX_I2C_REG_CONTROL_IFLG) {
> - status = readl(drv_data->reg_base + MV64XXX_I2C_REG_STATUS);
> + status = readl(drv_data->reg_base + drv_data->reg_offsets.status);
> mv64xxx_i2c_fsm(drv_data, status);
> mv64xxx_i2c_do_action(drv_data);
> rc = IRQ_HANDLED;
> @@ -495,6 +508,12 @@ static const struct i2c_algorithm mv64xxx_i2c_algo = {
> *
> *****************************************************************************
> */
> +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);
> +
> #ifdef CONFIG_OF
> static int
> mv64xxx_calc_freq(const int tclk, const int n, const int m)
> @@ -528,8 +547,10 @@ 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 +579,13 @@ 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;
> +
> + memcpy(&drv_data->reg_offsets, device->data, sizeof(drv_data->reg_offsets));
> +
> out:
> return rc;
> #endif
> @@ -565,7 +593,7 @@ 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 +639,9 @@ 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);
> + memcpy(&drv_data->reg_offsets, &mv64xxx_i2c_regs_mv64xxx, sizeof(drv_data->reg_offsets));
> } 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 +709,6 @@ 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,
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