[PATCH v2 02/10] i2c: OMAP: Add DT support for i2c controller
Shubhrajyoti
shubhrajyoti at ti.com
Thu Dec 22 19:29:09 EST 2011
Since it touches the driver file
+linux-i2c
On Friday 09 December 2011 07:32 PM, Benoit Cousson wrote:
> Add initial DT support to retrieve the frequency using a
> DT attribute instead of the pdata pointer if of_node exist.
>
> Add documentation for omap i2c controller binding.
>
> Based on original patches from Manju and Grant.
>
> Signed-off-by: Benoit Cousson <b-cousson at ti.com>
> Cc: Ben Dooks <ben-linux at fluff.org>
> ---
> Documentation/devicetree/bindings/i2c/omap-i2c.txt | 42 ++++++++
> drivers/i2c/busses/i2c-omap.c | 100 +++++++++++++-------
> 2 files changed, 107 insertions(+), 35 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/i2c/omap-i2c.txt
>
> diff --git a/Documentation/devicetree/bindings/i2c/omap-i2c.txt b/Documentation/devicetree/bindings/i2c/omap-i2c.txt
> new file mode 100644
> index 0000000..d259a17
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/omap-i2c.txt
> @@ -0,0 +1,42 @@
> +I2C for OMAP platforms
> +
> +Required properties :
> +- compatible : Must be "ti,omap3-i2c" or "ti,omap4-i2c"
> +- ti,hwmods : Must be "i2c<n>", n being the instance number (1-based)
> +- #address-cells = <1>;
> +- #size-cells = <0>;
> +
> +Recommended properties :
> +- clock-frequency : Desired I2C bus clock frequency in Hz. Otherwise
> + the default 100 kHz frequency will be used.
> +
> +Optional properties:
> +- Child nodes conforming to i2c bus binding
> +- ti,flags : u32: settings or errata relative to the i2c
> + 0x1: OMAP_I2C_FLAG_NO_FIFO
> + 0x2: OMAP_I2C_FLAG_SIMPLE_CLOCK
> + 0x4: OMAP_I2C_FLAG_16BIT_DATA_REG
> + 0x8: OMAP_I2C_FLAG_RESET_REGS_POSTIDLE
> + 0x10: OMAP_I2C_FLAG_APPLY_ERRATA_I207
> + 0x20: OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK
> + 0x40: OMAP_I2C_FLAG_FORCE_19200_INT_CLK
> + Valid for ti,omap3-i2c only:
> + 0x80: OMAP_I2C_FLAG_BUS_SHIFT_1: 8 bits registers
> + 0x100: OMAP_I2C_FLAG_BUS_SHIFT_2: 16 bits registers
> +
> +Note: Current implementation will fetch base address, irq and dma
> +from omap hwmod data base during device registration.
> +Future plan is to migrate hwmod data base contents into device tree
> +blob so that, all the required data will be used from device tree dts
> +file.
> +
> +Examples :
> +
> +i2c1: i2c at 0 {
> + compatible = "ti,omap3-i2c";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + ti,hwmods = "i2c1";
> + clock-frequency = <400000>;
> + ti,flags = <0x118>;
> +};
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index a43d002..b4a8eee 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -37,6 +37,8 @@
> #include <linux/platform_device.h>
> #include <linux/clk.h>
> #include <linux/io.h>
> +#include <linux/of_i2c.h>
> +#include <linux/of_device.h>
> #include <linux/slab.h>
> #include <linux/i2c-omap.h>
> #include <linux/pm_runtime.h>
> @@ -182,7 +184,9 @@ struct omap_i2c_dev {
> u32 latency; /* maximum mpu wkup latency */
> void (*set_mpu_wkup_lat)(struct device *dev,
> long latency);
> - u32 speed; /* Speed of bus in Khz */
> + u32 speed; /* Speed of bus in kHz */
> + u32 dtrev; /* extra revision from DT */
> + u32 flags;
> u16 cmd_err;
> u8 *buf;
> u8 *regs;
> @@ -266,11 +270,7 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>
> static void omap_i2c_unidle(struct omap_i2c_dev *dev)
> {
> - struct omap_i2c_bus_platform_data *pdata;
> -
> - pdata = dev->dev->platform_data;
> -
> - if (pdata->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> + if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> @@ -291,13 +291,10 @@ static void omap_i2c_unidle(struct omap_i2c_dev *dev)
>
> static void omap_i2c_idle(struct omap_i2c_dev *dev)
> {
> - struct omap_i2c_bus_platform_data *pdata;
> u16 iv;
>
> - pdata = dev->dev->platform_data;
> -
> dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
> - if (pdata->rev == OMAP_I2C_IP_VERSION_2)
> + if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
> omap_i2c_write_reg(dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, 1);
> else
> omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
> @@ -320,9 +317,6 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> unsigned long timeout;
> unsigned long internal_clk = 0;
> struct clk *fclk;
> - struct omap_i2c_bus_platform_data *pdata;
> -
> - pdata = dev->dev->platform_data;
>
> if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
> /* Disable I2C controller before soft reset */
> @@ -373,7 +367,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> }
> omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>
> - if (pdata->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
> + if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
> /*
> * The I2C functional clock is the armxor_ck, so there's
> * no need to get "armxor_ck" separately. Now, if OMAP2420
> @@ -397,7 +391,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> psc = fclk_rate / 12000000;
> }
>
> - if (!(pdata->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
> + if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
>
> /*
> * HSI2C controller internal clk rate should be 19.2 Mhz for
> @@ -406,7 +400,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> * The filter is iclk (fclk for HS) period.
> */
> if (dev->speed > 400 ||
> - pdata->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
> + dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
> internal_clk = 19200;
> else if (dev->speed > 100)
> internal_clk = 9600;
> @@ -475,7 +469,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>
> dev->errata = 0;
>
> - if (pdata->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
> + if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
> dev->errata |= I2C_OMAP_ERRATA_I207;
>
> /* Enable interrupts */
> @@ -484,7 +478,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
> OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
> (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
> omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> - if (pdata->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> + if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> dev->pscstate = psc;
> dev->scllstate = scll;
> dev->sclhstate = sclh;
> @@ -804,9 +798,6 @@ omap_i2c_isr(int this_irq, void *dev_id)
> u16 bits;
> u16 stat, w;
> int err, count = 0;
> - struct omap_i2c_bus_platform_data *pdata;
> -
> - pdata = dev->dev->platform_data;
>
> if (pm_runtime_suspended(dev->dev))
> return IRQ_NONE;
> @@ -875,7 +866,7 @@ complete:
> * Data reg in 2430, omap3 and
> * omap4 is 8 bit wide
> */
> - if (pdata->flags &
> + if (dev->flags &
> OMAP_I2C_FLAG_16BIT_DATA_REG) {
> if (dev->buf_len) {
> *dev->buf++ = w >> 8;
> @@ -918,7 +909,7 @@ complete:
> * Data reg in 2430, omap3 and
> * omap4 is 8 bit wide
> */
> - if (pdata->flags &
> + if (dev->flags &
> OMAP_I2C_FLAG_16BIT_DATA_REG) {
> if (dev->buf_len) {
> w |= *dev->buf++ << 8;
> @@ -965,6 +956,31 @@ static const struct i2c_algorithm omap_i2c_algo = {
> .functionality = omap_i2c_func,
> };
>
> +#ifdef CONFIG_OF
> +static struct omap_i2c_bus_platform_data omap3_pdata = {
> + .rev = OMAP_I2C_IP_VERSION_1,
> +};
> +
> +static struct omap_i2c_bus_platform_data omap4_pdata = {
> + .rev = OMAP_I2C_IP_VERSION_2,
> +};
> +
> +static const struct of_device_id omap_i2c_of_match[] = {
> + {
> + .compatible = "ti,omap4-i2c",
> + .data = &omap4_pdata,
> + },
> + {
> + .compatible = "ti,omap3-i2c",
> + .data = &omap3_pdata,
> + },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
> +#else
> +#define omap_i2c_of_match NULL
> +#endif
> +
> static int __devinit
> omap_i2c_probe(struct platform_device *pdev)
> {
> @@ -972,9 +988,10 @@ omap_i2c_probe(struct platform_device *pdev)
> struct i2c_adapter *adap;
> struct resource *mem, *irq, *ioarea;
> struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
> + struct device_node *node = pdev->dev.of_node;
> + const struct of_device_id *match;
> irq_handler_t isr;
> int r;
> - u32 speed = 0;
>
> /* NOTE: driver uses the static register mapping */
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> @@ -1001,15 +1018,24 @@ omap_i2c_probe(struct platform_device *pdev)
> goto err_release_region;
> }
>
> - if (pdata != NULL) {
> - speed = pdata->clkrate;
> + match = of_match_device(omap_i2c_of_match, &pdev->dev);
> + if (match) {
> + u32 freq = 100000; /* default to 100000 Hz */
> + pdata = match->data;
> +
> + of_property_read_u32(node, "clock-frequency", &freq);
> + /* convert DT freq value in Hz into kHz for speed */
> + dev->speed = freq / 1000;
> + of_property_read_u32(node, "ti,flags", &dev->flags);
> + dev->dtrev = pdata->rev;
> +
> + } else if (pdata != NULL) {
> + dev->speed = pdata->clkrate;
> + dev->flags = pdata->flags;
> dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
> - } else {
> - speed = 100; /* Default speed */
> - dev->set_mpu_wkup_lat = NULL;
> + dev->dtrev = pdata->rev;
> }
>
> - dev->speed = speed;
> dev->dev = &pdev->dev;
> dev->irq = irq->start;
> dev->base = ioremap(mem->start, resource_size(mem));
> @@ -1020,9 +1046,9 @@ omap_i2c_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, dev);
>
> - dev->reg_shift = (pdata->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
> + dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
>
> - if (pdata->rev == OMAP_I2C_IP_VERSION_2)
> + if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
> dev->regs = (u8 *)reg_map_ip_v2;
> else
> dev->regs = (u8 *)reg_map_ip_v1;
> @@ -1035,7 +1061,7 @@ omap_i2c_probe(struct platform_device *pdev)
> if (dev->rev <= OMAP_I2C_REV_ON_3430)
> dev->errata |= I2C_OMAP3_1P153;
>
> - if (!(pdata->flags & OMAP_I2C_FLAG_NO_FIFO)) {
> + if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
> u16 s;
>
> /* Set up the fifo size - Get total size */
> @@ -1057,7 +1083,7 @@ omap_i2c_probe(struct platform_device *pdev)
> /* calculate wakeup latency constraint for MPU */
> if (dev->set_mpu_wkup_lat != NULL)
> dev->latency = (1000000 * dev->fifo_size) /
> - (1000 * speed / 8);
> + (1000 * dev->speed / 8);
> }
>
> /* reset ASAP, clearing any IRQs */
> @@ -1073,7 +1099,7 @@ omap_i2c_probe(struct platform_device *pdev)
> }
>
> dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
> - pdata->rev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
> + dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
>
> pm_runtime_put(dev->dev);
>
> @@ -1084,6 +1110,7 @@ omap_i2c_probe(struct platform_device *pdev)
> strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
> adap->algo = &omap_i2c_algo;
> adap->dev.parent = &pdev->dev;
> + adap->dev.of_node = pdev->dev.of_node;
>
> /* i2c device drivers may be active on return from add_adapter() */
> adap->nr = pdev->id;
> @@ -1093,6 +1120,8 @@ omap_i2c_probe(struct platform_device *pdev)
> goto err_free_irq;
> }
>
> + of_i2c_register_devices(adap);
> +
> return 0;
>
> err_free_irq:
> @@ -1165,6 +1194,7 @@ static struct platform_driver omap_i2c_driver = {
> .name = "omap_i2c",
> .owner = THIS_MODULE,
> .pm = OMAP_I2C_PM_OPS,
> + .of_match_table = omap_i2c_of_match,
> },
> };
>
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