[PATCH v3 2/2] i2c: imx: Add Vybrid VF610 I2C controller support
Sascha Hauer
s.hauer at pengutronix.de
Mon Aug 5 04:30:50 EDT 2013
On Fri, Aug 02, 2013 at 12:44:08PM +0800, Jingchang Lu wrote:
> Add Freescale Vybrid VF610 I2C controller support to
> imx I2C driver framework.
> Some operation is different from imx I2C controller.
> The register offset, the i2c clock divider value table,
> the module enabling(I2CR_IEN) which is just invert with imx,
> and the interrupt flag(I2SR) clearing opcode is w1c on VF610
> but w0c on imx.
>
> Signed-off-by: Jason Jin <Jason.jin at freescale.com>
> Signed-off-by: Xiaochun Li <b41219 at freescale.com>
> Signed-off-by: Jingchang Lu <b35083 at freescale.com>
> ---
> changes in v3:
> Using struct naming the i2c clock {div, regval} pair.
> Using address shift handling registers address difference.
>
> changes in v2:
> Fix building section mismatch(es) warning.
>
> drivers/i2c/busses/i2c-imx.c | 146 ++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 122 insertions(+), 24 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index e242797..8f9981c 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -30,6 +30,8 @@
> * Copyright (C) 2007 RightHand Technologies, Inc.
> * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
> *
> + * Copyright 2013 Freescale Semiconductor, Inc.
> + *
> */
>
> /** Includes *******************************************************************
> @@ -62,13 +64,6 @@
> /* Default value */
> #define IMX_I2C_BIT_RATE 100000 /* 100kHz */
>
> -/* IMX I2C registers */
> -#define IMX_I2C_IADR 0x00 /* i2c slave address */
> -#define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
> -#define IMX_I2C_I2CR 0x08 /* i2c control */
> -#define IMX_I2C_I2SR 0x0C /* i2c status */
> -#define IMX_I2C_I2DR 0x10 /* i2c transfer data */
> -
> /* Bits of IMX I2C registers */
> #define I2SR_RXAK 0x01
> #define I2SR_IIF 0x02
> @@ -95,8 +90,12 @@
> *
> * Duplicated divider values removed from list
> */
> +struct imx_i2c_clk_pair {
> + u16 div;
> + u16 regval;
> +}i;
Converting this to a struct should be a separate patch. This is an
obvious cleanup which makes maintainers happy and more willing to take
the features you are adding later.
>
> -static u16 __initdata i2c_clk_div[50][2] = {
> +static struct imx_i2c_clk_pair imx_i2c_clk_div[] = {
> { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
> { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
> { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
> @@ -112,11 +111,63 @@ static u16 __initdata i2c_clk_div[50][2] = {
> { 3072, 0x1E }, { 3840, 0x1F }
> };
>
> +/* Vybrid VF610 clock divider, register value pairs */
> +static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = {
> + { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 },
> + { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 },
> + { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D },
> + { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 },
> + { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 },
> + { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 },
> + { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 },
> + { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 },
> + { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 },
> + { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B },
> + { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 },
> + { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 },
> + { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B },
> + { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A },
> + { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E },
> +};
> +
> enum imx_i2c_type {
> IMX1_I2C,
> IMX21_I2C,
> + VF610_I2C,
> };
>
> +struct imx_i2c_hwdata {
> + unsigned regshift;
> + struct imx_i2c_clk_pair *clk_div;
> + unsigned ndivs;
> + unsigned i2sr_clr_opcode;
> + unsigned i2cr_ien_opcode;
> +};
> +
> +struct imx_i2c_drvdata {
> + enum imx_i2c_type devtype;
> + struct imx_i2c_hwdata *hwdata;
> +};
> +
> +#define IMX_I2C_IADR (0x00 << i2c_imx->i2c_hwdata->regshift)
> +#define IMX_I2C_IFDR (0x01 << i2c_imx->i2c_hwdata->regshift)
> +#define IMX_I2C_I2CR (0x02 << i2c_imx->i2c_hwdata->regshift)
> +#define IMX_I2C_I2SR (0x03 << i2c_imx->i2c_hwdata->regshift)
> +#define IMX_I2C_I2DR (0x04 << i2c_imx->i2c_hwdata->regshift)
Macros should not assume there is a i2c_imx variable present in a
function. Instead, add static inline accessor functions.
> +
> +/*
> + * Interrupt flags clear operation differ between SoCs:
> + * - write zero to clear(w0c) INT flag on I.MX,
It's i.MX. With a Freescale mail address you should get this right ;)
> + * - but write one to clear(w1c) INT flag on Vybrid.
> + * I2C module enable operation also differ bteween SoCs:
s/bteween/between/
> + * - set I2CR_IEN bit enable the module on I.MX,
> + * - but clear I2CR_IEN bit enable the module on Vybrid.
> + */
> +#define I2SR_CLR_OPCODE_W0C 0x0
> +#define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF)
> +#define I2CR_IEN_OPCODE_0 0x0
> +#define I2CR_IEN_OPCODE_1 I2CR_IEN
> +
> struct imx_i2c_struct {
> struct i2c_adapter adapter;
> struct clk *clk;
> @@ -127,15 +178,52 @@ struct imx_i2c_struct {
> int stopped;
> unsigned int ifdr; /* IMX_I2C_IFDR */
> enum imx_i2c_type devtype;
> + struct imx_i2c_hwdata *i2c_hwdata;
> +};
> +
> +static struct imx_i2c_hwdata imx_i2c_hwdata = {
> + .regshift = 2,
> + .clk_div = imx_i2c_clk_div,
> + .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
> + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
> + .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
> +
> +};
unnecessary blank line
> +
> +static struct imx_i2c_hwdata vf610_i2c_hwdata = {
> + .regshift = 0,
> + .clk_div = vf610_i2c_clk_div,
> + .ndivs = ARRAY_SIZE(vf610_i2c_clk_div),
> + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C,
> + .i2cr_ien_opcode = I2CR_IEN_OPCODE_0,
> +
> +};
ditto
> +
> +static struct imx_i2c_drvdata imx_i2c_drvdata[] = {
> + [IMX1_I2C] = {
> + .devtype = IMX1_I2C,
> + .hwdata = &imx_i2c_hwdata
> + },
> + [IMX21_I2C] = {
> + .devtype = IMX21_I2C,
> + .hwdata = &imx_i2c_hwdata
> + },
> + [VF610_I2C] = {
> + .devtype = VF610_I2C,
> + .hwdata = &vf610_i2c_hwdata
> + },
> };
Why add this array?
>
> static struct platform_device_id imx_i2c_devtype[] = {
> {
> .name = "imx1-i2c",
> - .driver_data = IMX1_I2C,
> + .driver_data = (kernel_ulong_t)&imx_i2c_drvdata[IMX1_I2C],
You should reference imx_i2c_hwdata/vf610_i2c_hwdata directly here.
> }, {
> .name = "imx21-i2c",
> - .driver_data = IMX21_I2C,
> + .driver_data = (kernel_ulong_t)&imx_i2c_drvdata[IMX21_I2C],
> + }, {
> + .name = "vf610-i2c",
> + .driver_data = (kernel_ulong_t)&imx_i2c_drvdata[VF610_I2C],
> }, {
> /* sentinel */
> }
> @@ -145,6 +233,7 @@ MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
> static const struct of_device_id i2c_imx_dt_ids[] = {
> { .compatible = "fsl,imx1-i2c", .data = &imx_i2c_devtype[IMX1_I2C], },
> { .compatible = "fsl,imx21-i2c", .data = &imx_i2c_devtype[IMX21_I2C], },
> + { .compatible = "fsl,vf610-i2c", .data = &imx_i2c_devtype[VF610_I2C], },
> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids);
> @@ -215,9 +304,8 @@ static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
> clk_prepare_enable(i2c_imx->clk);
> writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
> /* Enable I2C controller */
> - writeb(0, i2c_imx->base + IMX_I2C_I2SR);
> - writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
> -
> + writeb(i2c_imx->i2c_hwdata->i2sr_clr_opcode, i2c_imx->base + IMX_I2C_I2SR);
> + writeb(i2c_imx->i2c_hwdata->i2cr_ien_opcode, i2c_imx->base + IMX_I2C_I2CR);
> /* Wait controller to be stable */
> udelay(50);
>
> @@ -260,7 +348,8 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
> }
>
> /* Disable I2C controller */
> - writeb(0, i2c_imx->base + IMX_I2C_I2CR);
> + writeb(i2c_imx->i2c_hwdata->i2cr_ien_opcode ^ I2CR_IEN,
> + i2c_imx->base + IMX_I2C_I2CR);
> clk_disable_unprepare(i2c_imx->clk);
> }
>
> @@ -270,19 +359,20 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> unsigned int i2c_clk_rate;
> unsigned int div;
> int i;
> + struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->i2c_hwdata->clk_div;
>
> /* Divider value calculation */
> i2c_clk_rate = clk_get_rate(i2c_imx->clk);
> div = (i2c_clk_rate + rate - 1) / rate;
> - if (div < i2c_clk_div[0][0])
> + if (div < i2c_clk_div[0].div)
> i = 0;
> - else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
> - i = ARRAY_SIZE(i2c_clk_div) - 1;
> + else if (div > i2c_clk_div[i2c_imx->i2c_hwdata->ndivs - 1].div)
> + i = i2c_imx->i2c_hwdata->ndivs - 1;
> else
> - for (i = 0; i2c_clk_div[i][0] < div; i++);
> + for (i = 0; i2c_clk_div[i].div < div; i++);
>
> /* Store divider value */
> - i2c_imx->ifdr = i2c_clk_div[i][1];
> + i2c_imx->ifdr = i2c_clk_div[i].regval;
>
> /*
> * There dummy delay is calculated.
> @@ -290,7 +380,7 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> * This delay is used in I2C bus disable function
> * to fix chip hardware bug.
> */
> - i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
> + i2c_imx->disable_delay = (500000U * i2c_clk_div[i].div
> + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
>
> /* dev_dbg() can't be used, because adapter is not yet registered */
> @@ -298,7 +388,7 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> dev_dbg(&i2c_imx->adapter.dev, "<%s> I2C_CLK=%d, REQ DIV=%d\n",
> __func__, i2c_clk_rate, div);
> dev_dbg(&i2c_imx->adapter.dev, "<%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
> - __func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
> + __func__, i2c_clk_div[i].regval, i2c_clk_div[i].div);
> #endif
> }
>
> @@ -312,6 +402,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
> /* save status register */
> i2c_imx->i2csr = temp;
> temp &= ~I2SR_IIF;
> + temp |= (i2c_imx->i2c_hwdata->i2sr_clr_opcode & I2SR_IIF);
> writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
> wake_up(&i2c_imx->queue);
> return IRQ_HANDLED;
> @@ -493,6 +584,7 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
> struct imx_i2c_struct *i2c_imx;
> struct resource *res;
> struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
> + struct imx_i2c_drvdata *drvdata;
> void __iomem *base;
> int irq, ret;
> u32 bitrate;
> @@ -519,7 +611,9 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
>
> if (of_id)
> pdev->id_entry = of_id->data;
This is wrong in the original driver code. This field should be changed
in a driver.
> - i2c_imx->devtype = pdev->id_entry->driver_data;
> + drvdata = (struct imx_i2c_drvdata *)pdev->id_entry->driver_data;
Unnecessary cast.
Sascha
--
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