[PATCH v6] ARM: davinci: i2c: add OF support
From: Heiko Schocher <hidden>
Date: 2012-07-17 08:40:47
Also in:
linux-devicetree, linux-i2c
Subsystem:
i2c subsystem, i2c subsystem host drivers, open firmware and flattened device tree bindings, the rest, ti davinci machine support · Maintainers:
Wolfram Sang, Andi Shyti, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds, Bartosz Golaszewski
add of support for the davinci i2c driver.
Signed-off-by: Heiko Schocher <redacted>
Signed-off-by: Sekhar Nori <redacted>
Cc: davinci-linux-open-source at linux.davincidsp.com
Cc: linux-arm-kernel at lists.infradead.org
Cc: devicetree-discuss at lists.ozlabs.org
Cc: linux-i2c at vger.kernel.org
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wolfram Sang <redacted>
Cc: Grant Likely <redacted>
Cc: Sekhar Nori <redacted>
Cc: Wolfgang Denk <redacted>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
---
- changes for v2:
- add comments from Sylwester Nawrocki [off-list ref]:
- use "cell-index" instead "id"
- OF_DEV_AUXDATA in the machine code, instead pre-define platform
device name
- add comment from Grant Likely:
- removed "id" resp. "cell-index" completely
- fixed documentation
- use of_match_ptr()
- use devm_kzalloc() for allocating plattform data mem
- fixed a whitespace issue
- no changes for v3
- changes for v4
remove "pinmux-handle" property as discussed here:
http://www.spinics.net/lists/arm-kernel/msg175701.html
with Nori Sekhar
- changes for v5
add comments from Grant Likely:
- do not change value of dev->dev->platform_data, instead
hold a copy in davinci_i2c_dev.
- changes for v6:
add comments from Sekhar Nori:
- removed unneccessary include
- merge patch from Sekhar Nori:
setup the newly introduced dev->pdata member correctly once in
probe -> i2c_get_plattformdata(() not needed, remove a lot of
checks for pdata in code
- add Signed-off-by: Sekhar Nori [off-list ref]
- patch no longer in patchserie, as it has no dependencies.
---
.../devicetree/bindings/arm/davinci/i2c.txt | 31 ++++++++++++
drivers/i2c/busses/i2c-davinci.c | 50 +++++++++++++++----
2 files changed, 70 insertions(+), 11 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/davinci/i2c.txt
diff --git a/Documentation/devicetree/bindings/arm/davinci/i2c.txt b/Documentation/devicetree/bindings/arm/davinci/i2c.txt
new file mode 100644
index 0000000..e98a025
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/davinci/i2c.txt@@ -0,0 +1,31 @@ +* Texas Instruments Davinci I2C + +This file provides information, what the device node for the +davinci i2c interface contain. + +Required properties: +- compatible: "ti,davinci-i2c"; +- reg : Offset and length of the register set for the device + +Recommended properties : +- interrupts : <a> standard interrupt property. +- clock-frequency : desired I2C bus clock frequency in Hz. + +Optional properties: +- bus-delay: bus delay in usec + +Example (enbw_cmc board): + i2c at 1c22000 { + compatible = "ti,davinci-i2c"; + reg = <0x22000 0x1000>; + clock-frequency = <100000>; + interrupts = <15>; + interrupt-parent = <&intc>; + #address-cells = <1>; + #size-cells = <0>; + + dtt at 48 { + compatible = "national,lm75"; + reg = <0x48>; + }; + };
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index a76d85f..8d4efce 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c@@ -38,6 +38,8 @@ #include <linux/slab.h> #include <linux/cpufreq.h> #include <linux/gpio.h> +#include <linux/of_i2c.h> +#include <linux/of_device.h> #include <mach/hardware.h> #include <mach/i2c.h>
@@ -114,6 +116,7 @@ struct davinci_i2c_dev { struct completion xfr_complete; struct notifier_block freq_transition; #endif + struct davinci_i2c_platform_data *pdata; }; /* default platform data to use if not supplied in the platform_device */
@@ -155,7 +158,7 @@ static void generic_i2c_clock_pulse(unsigned int scl_pin) static void i2c_recover_bus(struct davinci_i2c_dev *dev) { u32 flag = 0; - struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; + struct davinci_i2c_platform_data *pdata = dev->pdata; dev_err(dev->dev, "initiating i2c bus recovery\n"); /* Send NACK to the slave */
@@ -163,8 +166,7 @@ static void i2c_recover_bus(struct davinci_i2c_dev *dev) flag |= DAVINCI_I2C_MDR_NACK; /* write the data into mode register */ davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); - if (pdata) - generic_i2c_clock_pulse(pdata->scl_pin); + generic_i2c_clock_pulse(pdata->scl_pin); /* Send STOP */ flag = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); flag |= DAVINCI_I2C_MDR_STP;
@@ -187,7 +189,7 @@ static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) { - struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; + struct davinci_i2c_platform_data *pdata = dev->pdata; u16 psc; u32 clk; u32 d;
@@ -235,10 +237,7 @@ static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) */ static int i2c_davinci_init(struct davinci_i2c_dev *dev) { - struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; - - if (!pdata) - pdata = &davinci_i2c_platform_data_default; + struct davinci_i2c_platform_data *pdata = dev->pdata; /* put I2C into reset */ davinci_i2c_reset_ctrl(dev, 0);
@@ -308,13 +307,11 @@ static int i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); - struct davinci_i2c_platform_data *pdata = dev->dev->platform_data; + struct davinci_i2c_platform_data *pdata = dev->pdata; u32 flag; u16 w; int r; - if (!pdata) - pdata = &davinci_i2c_platform_data_default; /* Introduce a delay, required for some boards (e.g Davinci EVM) */ if (pdata->bus_delay) udelay(pdata->bus_delay);
@@ -635,6 +632,12 @@ static struct i2c_algorithm i2c_davinci_algo = { .functionality = i2c_davinci_func, }; +static const struct of_device_id davinci_i2c_of_match[] = { + {.compatible = "ti,davinci-i2c", }, + {}, +}; +MODULE_DEVICE_TABLE(of, davinci_i2c_of_match); + static int davinci_i2c_probe(struct platform_device *pdev) { struct davinci_i2c_dev *dev;
@@ -674,8 +677,30 @@ static int davinci_i2c_probe(struct platform_device *pdev) #endif dev->dev = get_device(&pdev->dev); dev->irq = irq->start; + dev->pdata = dev->dev->platform_data; platform_set_drvdata(pdev, dev); + if (!dev->pdata && pdev->dev.of_node) { + u32 prop; + + dev->pdata = devm_kzalloc(&pdev->dev, + sizeof(struct davinci_i2c_platform_data), GFP_KERNEL); + if (!dev->pdata) { + r = -ENOMEM; + goto err_free_mem; + } + memcpy(dev->pdata, &davinci_i2c_platform_data_default, + sizeof(struct davinci_i2c_platform_data)); + if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency", + &prop)) + dev->pdata->bus_freq = prop / 1000; + if (!of_property_read_u32(pdev->dev.of_node, "bus-delay", + &prop)) + dev->pdata->bus_delay = prop; + } else if (!dev->pdata) { + dev->pdata = &davinci_i2c_platform_data_default; + } + dev->clk = clk_get(&pdev->dev, NULL); if (IS_ERR(dev->clk)) { r = -ENODEV;
@@ -711,6 +736,7 @@ static int davinci_i2c_probe(struct platform_device *pdev) adap->algo = &i2c_davinci_algo; adap->dev.parent = &pdev->dev; adap->timeout = DAVINCI_I2C_TIMEOUT; + adap->dev.of_node = pdev->dev.of_node; adap->nr = pdev->id; r = i2c_add_numbered_adapter(adap);
@@ -718,6 +744,7 @@ static int davinci_i2c_probe(struct platform_device *pdev) dev_err(&pdev->dev, "failure adding adapter\n"); goto err_free_irq; } + of_i2c_register_devices(adap); return 0;
@@ -809,6 +836,7 @@ static struct platform_driver davinci_i2c_driver = { .name = "i2c_davinci", .owner = THIS_MODULE, .pm = davinci_i2c_pm_ops, + .of_match_table = of_match_ptr(davinci_i2c_of_match), }, };
--
1.7.7.6