2017-08-02 22:19:28

by Franklin S Cooper Jr

[permalink] [raw]
Subject: [PATCH 0/4] ARM: dts: keystone-k2g: Add I2C support for 66AK2G

Add I2C support to 66AK2G. Primary requirement is to add PM
Runtime support to the driver.

This has been tested on following platforms by performing simple i2c test
such as i2c detect and reading on board i2c devices:
K2G GP evm
OMAPL138
K2L GP EVM

and boot tested on:
K2E GP EVM
K2HK GP EVM

Franklin S Cooper Jr (3):
i2c: davinci: Preserve return value of devm_clk_get
i2c: davinci: Add PM Runtime Support
dt-bindings: i2c: i2c-davinci: Update binding for 66AK2Gx pwr dm
property

Vitaly Andrianov (1):
ARM: dts: keystone-k2g: Add I2C nodes

.../devicetree/bindings/i2c/i2c-davinci.txt | 12 +++++
arch/arm/boot/dts/keystone-k2g.dtsi | 36 +++++++++++++
drivers/i2c/busses/i2c-davinci.c | 63 ++++++++++++++++++----
3 files changed, 102 insertions(+), 9 deletions(-)

--
2.9.4.dirty


2017-08-02 22:19:01

by Franklin S Cooper Jr

[permalink] [raw]
Subject: [PATCH 1/4] i2c: davinci: Preserve return value of devm_clk_get

The i2c driver can run into driver dependency issues if its loaded
before a clock driver it depends on. Therefore, EPROBE_DEFER may be
returned by devm_clk_get and should be returned in probe to allow the
kernel to reprobe the driver at a later time. This patch allows the error
value returned by devm_clk_get to be passed through and not overwritten.

Reviewed-by: Grygorii Strashko <[email protected]>
Signed-off-by: Franklin S Cooper Jr <[email protected]>
Signed-off-by: Sekhar Nori <[email protected]>
---
drivers/i2c/busses/i2c-davinci.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 9e7ef5c..5749aac 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -801,7 +801,7 @@ static int davinci_i2c_probe(struct platform_device *pdev)

dev->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk))
- return -ENODEV;
+ return PTR_ERR(dev->clk);
clk_prepare_enable(dev->clk);

mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
--
2.9.4.dirty

2017-08-02 22:19:09

by Franklin S Cooper Jr

[permalink] [raw]
Subject: [PATCH 4/4] ARM: dts: keystone-k2g: Add I2C nodes

From: Vitaly Andrianov <[email protected]>

Add nodes for the various I2C instances.

Signed-off-by: Vitaly Andrianov <[email protected]>
[[email protected]: Add power domain and clock properties]
Signed-off-by: Dave Gerlach <[email protected]>
[[email protected]: Update subject and commit message]
Signed-off-by: Franklin S Cooper Jr <[email protected]>
---
arch/arm/boot/dts/keystone-k2g.dtsi | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)

diff --git a/arch/arm/boot/dts/keystone-k2g.dtsi b/arch/arm/boot/dts/keystone-k2g.dtsi
index bf4d1fa..5c0acf37 100644
--- a/arch/arm/boot/dts/keystone-k2g.dtsi
+++ b/arch/arm/boot/dts/keystone-k2g.dtsi
@@ -27,6 +27,9 @@

aliases {
serial0 = &uart0;
+ i2c0 = &i2c0;
+ i2c1 = &i2c1;
+ i2c2 = &i2c2;
};

cpus {
@@ -113,6 +116,39 @@
status = "disabled";
};

+ i2c0: i2c@2530000 {
+ compatible = "ti,keystone-i2c";
+ reg = <0x02530000 0x400>;
+ clocks = <&k2g_clks 0x003a 0>;
+ power-domains = <&k2g_pds 0x003a>;
+ interrupts = <GIC_SPI 88 IRQ_TYPE_EDGE_RISING>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ };
+
+ i2c1: i2c@2530400 {
+ compatible = "ti,keystone-i2c";
+ reg = <0x02530400 0x400>;
+ clocks = <&k2g_clks 0x003b 0>;
+ power-domains = <&k2g_pds 0x003b>;
+ interrupts = <GIC_SPI 89 IRQ_TYPE_EDGE_RISING>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ };
+
+ i2c2: i2c@2530800 {
+ compatible = "ti,keystone-i2c";
+ reg = <0x02530800 0x400>;
+ clocks = <&k2g_clks 0x003c 0>;
+ power-domains = <&k2g_pds 0x003c>;
+ interrupts = <GIC_SPI 90 IRQ_TYPE_EDGE_RISING>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ };
+
kirq0: keystone_irq@026202a0 {
compatible = "ti,keystone-irq";
interrupts = <GIC_SPI 1 IRQ_TYPE_EDGE_RISING>;
--
2.9.4.dirty

2017-08-02 22:20:03

by Franklin S Cooper Jr

[permalink] [raw]
Subject: [PATCH 3/4] dt-bindings: i2c: i2c-davinci: Update binding for 66AK2Gx pwr dm property

Add pm-domains property which is required for 66AK2Gx. Also document 66AK2G
unique clocks property usage.

Signed-off-by: Franklin S Cooper Jr <[email protected]>
---
Documentation/devicetree/bindings/i2c/i2c-davinci.txt | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/i2c-davinci.txt b/Documentation/devicetree/bindings/i2c/i2c-davinci.txt
index 5b123e0..64e6e65 100644
--- a/Documentation/devicetree/bindings/i2c/i2c-davinci.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-davinci.txt
@@ -6,6 +6,18 @@ davinci/keystone i2c interface contains.
Required properties:
- compatible: "ti,davinci-i2c" or "ti,keystone-i2c";
- reg : Offset and length of the register set for the device
+- clocks: I2C functional clock phandle.
+ For 66AK2G this property should be set per binding,
+ Documentation/devicetree/bindings/clock/ti,sci-clk.txt
+
+SoC-specific Required Properties:
+
+The following are mandatory properties for Keystone 2 66AK2G SoCs only:
+
+- power-domains: Should contain a phandle to a PM domain provider node
+ and an args specifier containing the I2C device id
+ value. This property is as per the binding,
+ Documentation/devicetree/bindings/soc/ti/sci-pm-domain.txt

Recommended properties :
- interrupts : standard interrupt property.
--
2.9.4.dirty

2017-08-02 22:19:55

by Franklin S Cooper Jr

[permalink] [raw]
Subject: [PATCH 2/4] i2c: davinci: Add PM Runtime Support

This patch adds PM runtime support to the I2C Davinci driver.

Reviewed-by: Grygorii Strashko <[email protected]>
Signed-off-by: Franklin S Cooper Jr <[email protected]>
Signed-off-by: Sekhar Nori <[email protected]>
---
drivers/i2c/busses/i2c-davinci.c | 61 ++++++++++++++++++++++++++++++++++------
1 file changed, 53 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 5749aac..62ff869 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -36,6 +36,7 @@
#include <linux/gpio.h>
#include <linux/of_device.h>
#include <linux/platform_data/i2c-davinci.h>
+#include <linux/pm_runtime.h>

/* ----- global defines ----------------------------------------------- */

@@ -122,6 +123,9 @@
/* set the SDA GPIO low */
#define DAVINCI_I2C_DCLR_PDCLR1 BIT(1)

+/* timeout for pm runtime autosuspend */
+#define DAVINCI_I2C_PM_TIMEOUT 1000 /* ms */
+
struct davinci_i2c_dev {
struct device *dev;
void __iomem *base;
@@ -541,10 +545,17 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)

dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);

+ ret = pm_runtime_get_sync(dev->dev);
+ if (ret < 0) {
+ dev_err(dev->dev, "Failed to runtime_get device: %d\n", ret);
+ pm_runtime_put_noidle(dev->dev);
+ return ret;
+ }
+
ret = i2c_davinci_wait_bus_not_busy(dev);
if (ret < 0) {
dev_warn(dev->dev, "timeout waiting for bus ready\n");
- return ret;
+ goto out;
}

for (i = 0; i < num; i++) {
@@ -552,14 +563,19 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
dev_dbg(dev->dev, "%s [%d/%d] ret: %d\n", __func__, i + 1, num,
ret);
if (ret < 0)
- return ret;
+ goto out;
}

+ ret = num;
#ifdef CONFIG_CPU_FREQ
complete(&dev->xfr_complete);
#endif

- return num;
+out:
+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
+ return ret;
}

static u32 i2c_davinci_func(struct i2c_adapter *adap)
@@ -599,6 +615,9 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
int count = 0;
u16 w;

+ if (pm_runtime_suspended(dev->dev))
+ return IRQ_NONE;
+
while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) {
dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat);
if (count++ == 100) {
@@ -802,7 +821,6 @@ static int davinci_i2c_probe(struct platform_device *pdev)
dev->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(dev->clk))
return PTR_ERR(dev->clk);
- clk_prepare_enable(dev->clk);

mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
dev->base = devm_ioremap_resource(&pdev->dev, mem);
@@ -811,6 +829,17 @@ static int davinci_i2c_probe(struct platform_device *pdev)
goto err_unuse_clocks;
}

+ pm_runtime_enable(dev->dev);
+ pm_runtime_set_autosuspend_delay(dev->dev,
+ DAVINCI_I2C_PM_TIMEOUT);
+ pm_runtime_use_autosuspend(dev->dev);
+
+ r = pm_runtime_get_sync(dev->dev);
+ if (r < 0) {
+ dev_err(dev->dev, "failed to runtime_get device: %d\n", r);
+ goto err_unuse_clocks;
+ }
+
i2c_davinci_init(dev);

r = devm_request_irq(&pdev->dev, dev->irq, i2c_davinci_isr, 0,
@@ -849,10 +878,16 @@ static int davinci_i2c_probe(struct platform_device *pdev)
if (r)
goto err_unuse_clocks;

+ pm_runtime_mark_last_busy(dev->dev);
+ pm_runtime_put_autosuspend(dev->dev);
+
return 0;

err_unuse_clocks:
- clk_disable_unprepare(dev->clk);
+ pm_runtime_dont_use_autosuspend(dev->dev);
+ pm_runtime_put_sync(dev->dev);
+ pm_runtime_disable(dev->dev);
+
dev->clk = NULL;
return r;
}
@@ -860,16 +895,26 @@ static int davinci_i2c_probe(struct platform_device *pdev)
static int davinci_i2c_remove(struct platform_device *pdev)
{
struct davinci_i2c_dev *dev = platform_get_drvdata(pdev);
+ int ret;

i2c_davinci_cpufreq_deregister(dev);

i2c_del_adapter(&dev->adapter);

- clk_disable_unprepare(dev->clk);
+ ret = pm_runtime_get_sync(&pdev->dev);
+ if (ret < 0) {
+ pm_runtime_put_noidle(&pdev->dev);
+ return ret;
+ }
+
dev->clk = NULL;

davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0);

+ pm_runtime_dont_use_autosuspend(dev->dev);
+ pm_runtime_put_sync(dev->dev);
+ pm_runtime_disable(dev->dev);
+
return 0;
}

@@ -881,7 +926,6 @@ static int davinci_i2c_suspend(struct device *dev)

/* put I2C into reset */
davinci_i2c_reset_ctrl(i2c_dev, 0);
- clk_disable_unprepare(i2c_dev->clk);

return 0;
}
@@ -891,7 +935,6 @@ static int davinci_i2c_resume(struct device *dev)
struct platform_device *pdev = to_platform_device(dev);
struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev);

- clk_prepare_enable(i2c_dev->clk);
/* take I2C out of reset */
davinci_i2c_reset_ctrl(i2c_dev, 1);

@@ -901,6 +944,8 @@ static int davinci_i2c_resume(struct device *dev)
static const struct dev_pm_ops davinci_i2c_pm = {
.suspend = davinci_i2c_suspend,
.resume = davinci_i2c_resume,
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
};

#define davinci_i2c_pm_ops (&davinci_i2c_pm)
--
2.9.4.dirty

2017-08-10 16:36:50

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [PATCH 3/4] dt-bindings: i2c: i2c-davinci: Update binding for 66AK2Gx pwr dm property

On Wed, Aug 02, 2017 at 05:17:52PM -0500, Franklin S Cooper Jr wrote:
> Add pm-domains property which is required for 66AK2Gx. Also document 66AK2G
> unique clocks property usage.
>
> Signed-off-by: Franklin S Cooper Jr <[email protected]>
> ---
> Documentation/devicetree/bindings/i2c/i2c-davinci.txt | 12 ++++++++++++
> 1 file changed, 12 insertions(+)

Acked-by: Rob Herring <[email protected]>

2017-08-11 22:01:22

by Grygorii Strashko

[permalink] [raw]
Subject: Re: [PATCH 1/4] i2c: davinci: Preserve return value of devm_clk_get



On 08/02/2017 05:17 PM, Franklin S Cooper Jr wrote:
> The i2c driver can run into driver dependency issues if its loaded
> before a clock driver it depends on. Therefore, EPROBE_DEFER may be
> returned by devm_clk_get and should be returned in probe to allow the
> kernel to reprobe the driver at a later time. This patch allows the error
> value returned by devm_clk_get to be passed through and not overwritten.
>
> Reviewed-by: Grygorii Strashko <[email protected]>
> Signed-off-by: Franklin S Cooper Jr <[email protected]>
> Signed-off-by: Sekhar Nori <[email protected]>

I think it's better to drop internal tags.

Reviewed-by: Grygorii Strashko <[email protected]>

> ---
> drivers/i2c/busses/i2c-davinci.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
> index 9e7ef5c..5749aac 100644
> --- a/drivers/i2c/busses/i2c-davinci.c
> +++ b/drivers/i2c/busses/i2c-davinci.c
> @@ -801,7 +801,7 @@ static int davinci_i2c_probe(struct platform_device *pdev)
>
> dev->clk = devm_clk_get(&pdev->dev, NULL);
> if (IS_ERR(dev->clk))
> - return -ENODEV;
> + return PTR_ERR(dev->clk);
> clk_prepare_enable(dev->clk);
>
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>

--
regards,
-grygorii

2017-08-11 22:11:58

by Grygorii Strashko

[permalink] [raw]
Subject: Re: [PATCH 2/4] i2c: davinci: Add PM Runtime Support



On 08/02/2017 05:17 PM, Franklin S Cooper Jr wrote:
> This patch adds PM runtime support to the I2C Davinci driver.
>
> Reviewed-by: Grygorii Strashko <[email protected]>
> Signed-off-by: Franklin S Cooper Jr <[email protected]>
> Signed-off-by: Sekhar Nori <[email protected]>
> ---
> drivers/i2c/busses/i2c-davinci.c | 61 ++++++++++++++++++++++++++++++++++------
> 1 file changed, 53 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
> index 5749aac..62ff869 100644
> --- a/drivers/i2c/busses/i2c-davinci.c
> +++ b/drivers/i2c/busses/i2c-davinci.c
> @@ -36,6 +36,7 @@
> #include <linux/gpio.h>
> #include <linux/of_device.h>
> #include <linux/platform_data/i2c-davinci.h>
> +#include <linux/pm_runtime.h>
>
> /* ----- global defines ----------------------------------------------- */
>
> @@ -122,6 +123,9 @@
> /* set the SDA GPIO low */
> #define DAVINCI_I2C_DCLR_PDCLR1 BIT(1)
>
> +/* timeout for pm runtime autosuspend */
> +#define DAVINCI_I2C_PM_TIMEOUT 1000 /* ms */
> +
> struct davinci_i2c_dev {
> struct device *dev;
> void __iomem *base;
> @@ -541,10 +545,17 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
>
> dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num);
>
> + ret = pm_runtime_get_sync(dev->dev);
> + if (ret < 0) {
> + dev_err(dev->dev, "Failed to runtime_get device: %d\n", ret);
> + pm_runtime_put_noidle(dev->dev);
> + return ret;
> + }
> +
> ret = i2c_davinci_wait_bus_not_busy(dev);
> if (ret < 0) {
> dev_warn(dev->dev, "timeout waiting for bus ready\n");
> - return ret;
> + goto out;
> }
>
> for (i = 0; i < num; i++) {
> @@ -552,14 +563,19 @@ i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
> dev_dbg(dev->dev, "%s [%d/%d] ret: %d\n", __func__, i + 1, num,
> ret);
> if (ret < 0)
> - return ret;
> + goto out;
> }
>
> + ret = num;
> #ifdef CONFIG_CPU_FREQ
> complete(&dev->xfr_complete);
> #endif
>
> - return num;
> +out:
> + pm_runtime_mark_last_busy(dev->dev);
> + pm_runtime_put_autosuspend(dev->dev);
> +
> + return ret;
> }
>
> static u32 i2c_davinci_func(struct i2c_adapter *adap)
> @@ -599,6 +615,9 @@ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id)
> int count = 0;
> u16 w;
>
> + if (pm_runtime_suspended(dev->dev))
> + return IRQ_NONE;
> +
> while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) {
> dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat);
> if (count++ == 100) {
> @@ -802,7 +821,6 @@ static int davinci_i2c_probe(struct platform_device *pdev)
> dev->clk = devm_clk_get(&pdev->dev, NULL);
> if (IS_ERR(dev->clk))
> return PTR_ERR(dev->clk);
> - clk_prepare_enable(dev->clk);
>
> mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> dev->base = devm_ioremap_resource(&pdev->dev, mem);
> @@ -811,6 +829,17 @@ static int davinci_i2c_probe(struct platform_device *pdev)
> goto err_unuse_clocks;
> }
>
> + pm_runtime_enable(dev->dev);
> + pm_runtime_set_autosuspend_delay(dev->dev,
> + DAVINCI_I2C_PM_TIMEOUT);
> + pm_runtime_use_autosuspend(dev->dev);

Pls, move autosuspend configuration before pm_runtime_enable()

> +
> + r = pm_runtime_get_sync(dev->dev);
> + if (r < 0) {
> + dev_err(dev->dev, "failed to runtime_get device: %d\n", r);
> + goto err_unuse_clocks;
> + }
> +

Otherwise looks good to me.

--
regards,
-grygorii

2017-08-11 22:19:02

by Grygorii Strashko

[permalink] [raw]
Subject: Re: [PATCH 4/4] ARM: dts: keystone-k2g: Add I2C nodes



On 08/02/2017 05:17 PM, Franklin S Cooper Jr wrote:
> From: Vitaly Andrianov <[email protected]>
>
> Add nodes for the various I2C instances.
>
> Signed-off-by: Vitaly Andrianov <[email protected]>
> [[email protected]: Add power domain and clock properties]
> Signed-off-by: Dave Gerlach <[email protected]>
> [[email protected]: Update subject and commit message]
> Signed-off-by: Franklin S Cooper Jr <[email protected]>

It might be better to send this patch separately as it will
go to the different tree.

Reviewed-by: Grygorii Strashko <[email protected]>

> ---
> arch/arm/boot/dts/keystone-k2g.dtsi | 36 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 36 insertions(+)
>
> diff --git a/arch/arm/boot/dts/keystone-k2g.dtsi b/arch/arm/boot/dts/keystone-k2g.dtsi
> index bf4d1fa..5c0acf37 100644
> --- a/arch/arm/boot/dts/keystone-k2g.dtsi
> +++ b/arch/arm/boot/dts/keystone-k2g.dtsi
> @@ -27,6 +27,9 @@
>
> aliases {
> serial0 = &uart0;
> + i2c0 = &i2c0;
> + i2c1 = &i2c1;
> + i2c2 = &i2c2;
> };
>
> cpus {
> @@ -113,6 +116,39 @@
> status = "disabled";
> };
>
> + i2c0: i2c@2530000 {
> + compatible = "ti,keystone-i2c";
> + reg = <0x02530000 0x400>;
> + clocks = <&k2g_clks 0x003a 0>;
> + power-domains = <&k2g_pds 0x003a>;
> + interrupts = <GIC_SPI 88 IRQ_TYPE_EDGE_RISING>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + status = "disabled";
> + };
> +
> + i2c1: i2c@2530400 {
> + compatible = "ti,keystone-i2c";
> + reg = <0x02530400 0x400>;
> + clocks = <&k2g_clks 0x003b 0>;
> + power-domains = <&k2g_pds 0x003b>;
> + interrupts = <GIC_SPI 89 IRQ_TYPE_EDGE_RISING>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + status = "disabled";
> + };
> +
> + i2c2: i2c@2530800 {
> + compatible = "ti,keystone-i2c";
> + reg = <0x02530800 0x400>;
> + clocks = <&k2g_clks 0x003c 0>;
> + power-domains = <&k2g_pds 0x003c>;
> + interrupts = <GIC_SPI 90 IRQ_TYPE_EDGE_RISING>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + status = "disabled";
> + };
> +
> kirq0: keystone_irq@026202a0 {
> compatible = "ti,keystone-irq";
> interrupts = <GIC_SPI 1 IRQ_TYPE_EDGE_RISING>;
>

--
regards,
-grygorii