Re: [RFC 04/12] phy: Add simple-phy driver
Hi, On Friday 25 October 2013 01:21 PM, Tomasz Stanislawski wrote: Hi, Please refer to the comments below. On 10/24/2013 05:52 PM, Kishon Vijay Abraham I wrote: Hi, On Monday 21 October 2013 07:48 PM, Tomasz Stanislawski wrote: Add simple-phy driver to support a single register PHY interfaces present on Exynos4 SoC. How are these PHY interfaces modelled in the SoC? Where does the register actually reside? Initially, I was planning to add PHY for HDMI_PHY register in power management register set on s5pv310 soc. If that register is part of the power management register space, I don't think it justifies creating a PHY driver for it. However other PHYs use very similar interface (setting bit 0). This includes DAC_PHY, ADC_PHY, PCIe_PHY, SATA_PHY. Moreover it suits well to USBDEVICE_PHY, USBHOST_PHY. How is it currently being done for these drivers? Is it being done in the patches sent by Kamil or Vivek? Thanks Kishon -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC 04/12] phy: Add simple-phy driver
Hi,
Please refer to the comments below.
On 10/24/2013 05:52 PM, Kishon Vijay Abraham I wrote:
> Hi,
>
> On Monday 21 October 2013 07:48 PM, Tomasz Stanislawski wrote:
>> Add simple-phy driver to support a single register
>> PHY interfaces present on Exynos4 SoC.
>
> How are these PHY interfaces modelled in the SoC? Where does the register
> actually reside?
Initially, I was planning to add PHY for HDMI_PHY register in
power management register set on s5pv310 soc.
However other PHYs use very similar interface (setting bit 0).
This includes DAC_PHY, ADC_PHY, PCIe_PHY, SATA_PHY.
Moreover it suits well to USBDEVICE_PHY, USBHOST_PHY.
That is why I thought about using something more generic
to handle all those phys without introducing a herd of
200-lines-long drivers.
>>
>> Signed-off-by: Tomasz Stanislawski
>> ---
>> drivers/phy/Kconfig |5 ++
>> drivers/phy/Makefile |1 +
>> drivers/phy/phy-simple.c | 128
>> ++
>> 3 files changed, 134 insertions(+)
>> create mode 100644 drivers/phy/phy-simple.c
>>
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index ac239ac..619c657 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -38,4 +38,9 @@ config TWL4030_USB
>>This transceiver supports high and full speed devices plus,
>>in host mode, low speed.
>>
>> +config PHY_SIMPLE
>> +tristate "Simple PHY driver"
>
> This is too generic a name to be used. Lets name it something specific to what
> it is used for (EXYNOS/HDMI.. ?).
Ok. It could be renamed to EXYNOS-SIMPLE-PHY or EXYNOS-1BIT-PHY or
EXYNOS-GENERIC-PHY
or something similar. Any ideas?
>> +help
>> + Support for PHY controllers configured using single register.
>> +
>> endmenu
>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>> index 0dd8a98..3d68e19 100644
>> --- a/drivers/phy/Makefile
>> +++ b/drivers/phy/Makefile
>> @@ -5,3 +5,4 @@
>> obj-$(CONFIG_GENERIC_PHY) += phy-core.o
>> obj-$(CONFIG_OMAP_USB2) += phy-omap-usb2.o
>> obj-$(CONFIG_TWL4030_USB) += phy-twl4030-usb.o
>> +obj-$(CONFIG_PHY_SIMPLE)+= phy-simple.o
>> diff --git a/drivers/phy/phy-simple.c b/drivers/phy/phy-simple.c
>> new file mode 100644
>> index 000..4a28af7
>> --- /dev/null
>> +++ b/drivers/phy/phy-simple.c
>> @@ -0,0 +1,128 @@
>> +/*
>> + * Simple PHY driver
>> + *
>> + * Copyright (C) 2013 Samsung Electronics Co., Ltd.
>> + * Author: Tomasz Stanislawski
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#include
>> +#include
>> +#include
>> +#include
>> +#include
>> +#include
>> +#include
>> +#include
>> +
>> +struct simple_phy {
>> +spinlock_t slock;
>> +u32 on_value;
>> +u32 off_value;
>> +u32 mask;
>> +void __iomem *regs;
>> +};
>> +
>> +static int sphy_set(struct simple_phy *sphy, bool on)
>> +{
>> +u32 reg;
>> +
>> +spin_lock(&sphy->slock);
>
> Lets add spin_lock only when it is absolutely necessary. When your PHY
> provider
> implements only a single PHY, it is not needed. phy_power_on and phy_power_off
> is already protected by the framework.
ok
>> +
>> +reg = readl(sphy->regs);
>> +reg &= ~sphy->mask;
>> +reg |= sphy->mask & (on ? sphy->on_value : sphy->off_value);
>> +writel(reg, sphy->regs);
>> +
>> +spin_unlock(&sphy->slock);
>> +
>> +return 0;
>> +}
>> +
>> +static int simple_phy_power_on(struct phy *phy)
>> +{
>> +return sphy_set(phy_get_drvdata(phy), 1);
>> +}
>> +
>> +static int simple_phy_power_off(struct phy *phy)
>> +{
>> +return sphy_set(phy_get_drvdata(phy), 0);
>> +}
>> +
>> +static struct phy_ops simple_phy_ops = {
>> +.power_on = simple_phy_power_on,
>> +.power_off = simple_phy_power_off,
>> +.owner = THIS_MODULE,
>> +};
>> +
>> +static int simple_phy_probe(struct platform_device *pdev)
>> +{
>> +struct device *dev = &pdev->dev;
>> +struct simple_phy *sphy;
>> +struct resource *res;
>> +struct phy_provider *phy_provider;
>> +struct phy *phy;
>> +
>> +sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
>> +if (!sphy)
>> +return -ENOMEM;
>> +
>> +res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +
>> +sphy->regs = devm_ioremap_resource(dev, res);
>> +if (IS_ERR(sphy->regs)) {
>> +dev_err(dev, "failed to ioremap registers\n");
>> +return PTR_ERR(sphy->regs);
>> +}
>> +
>> +spin_lock_init(&sphy->slock);
>> +
>> +phy_provider = devm_of_phy_provider_register(dev, NULL);
>
> pass 'of_phy_simple_xlate' instead of NULL.
>> +if (IS_ERR(phy_provider)) {
>> +dev_err(dev, "failed to register PHY provider\n");
>> +return PTR_ERR(phy_provider);
>> +}
>> +
>> +phy = devm_phy_create(dev, &simple_phy_ops, NULL);
>>
Re: [RFC 04/12] phy: Add simple-phy driver
Hi,
On Monday 21 October 2013 07:48 PM, Tomasz Stanislawski wrote:
> Add simple-phy driver to support a single register
> PHY interfaces present on Exynos4 SoC.
How are these PHY interfaces modelled in the SoC? Where does the register
actually reside?
>
> Signed-off-by: Tomasz Stanislawski
> ---
> drivers/phy/Kconfig |5 ++
> drivers/phy/Makefile |1 +
> drivers/phy/phy-simple.c | 128
> ++
> 3 files changed, 134 insertions(+)
> create mode 100644 drivers/phy/phy-simple.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index ac239ac..619c657 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -38,4 +38,9 @@ config TWL4030_USB
> This transceiver supports high and full speed devices plus,
> in host mode, low speed.
>
> +config PHY_SIMPLE
> + tristate "Simple PHY driver"
This is too generic a name to be used. Lets name it something specific to what
it is used for (EXYNOS/HDMI.. ?).
> + help
> + Support for PHY controllers configured using single register.
> +
> endmenu
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 0dd8a98..3d68e19 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -5,3 +5,4 @@
> obj-$(CONFIG_GENERIC_PHY)+= phy-core.o
> obj-$(CONFIG_OMAP_USB2) += phy-omap-usb2.o
> obj-$(CONFIG_TWL4030_USB)+= phy-twl4030-usb.o
> +obj-$(CONFIG_PHY_SIMPLE) += phy-simple.o
> diff --git a/drivers/phy/phy-simple.c b/drivers/phy/phy-simple.c
> new file mode 100644
> index 000..4a28af7
> --- /dev/null
> +++ b/drivers/phy/phy-simple.c
> @@ -0,0 +1,128 @@
> +/*
> + * Simple PHY driver
> + *
> + * Copyright (C) 2013 Samsung Electronics Co., Ltd.
> + * Author: Tomasz Stanislawski
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +#include
> +
> +struct simple_phy {
> + spinlock_t slock;
> + u32 on_value;
> + u32 off_value;
> + u32 mask;
> + void __iomem *regs;
> +};
> +
> +static int sphy_set(struct simple_phy *sphy, bool on)
> +{
> + u32 reg;
> +
> + spin_lock(&sphy->slock);
Lets add spin_lock only when it is absolutely necessary. When your PHY provider
implements only a single PHY, it is not needed. phy_power_on and phy_power_off
is already protected by the framework.
> +
> + reg = readl(sphy->regs);
> + reg &= ~sphy->mask;
> + reg |= sphy->mask & (on ? sphy->on_value : sphy->off_value);
> + writel(reg, sphy->regs);
> +
> + spin_unlock(&sphy->slock);
> +
> + return 0;
> +}
> +
> +static int simple_phy_power_on(struct phy *phy)
> +{
> + return sphy_set(phy_get_drvdata(phy), 1);
> +}
> +
> +static int simple_phy_power_off(struct phy *phy)
> +{
> + return sphy_set(phy_get_drvdata(phy), 0);
> +}
> +
> +static struct phy_ops simple_phy_ops = {
> + .power_on = simple_phy_power_on,
> + .power_off = simple_phy_power_off,
> + .owner = THIS_MODULE,
> +};
> +
> +static int simple_phy_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct simple_phy *sphy;
> + struct resource *res;
> + struct phy_provider *phy_provider;
> + struct phy *phy;
> +
> + sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
> + if (!sphy)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> + sphy->regs = devm_ioremap_resource(dev, res);
> + if (IS_ERR(sphy->regs)) {
> + dev_err(dev, "failed to ioremap registers\n");
> + return PTR_ERR(sphy->regs);
> + }
> +
> + spin_lock_init(&sphy->slock);
> +
> + phy_provider = devm_of_phy_provider_register(dev, NULL);
pass 'of_phy_simple_xlate' instead of NULL.
> + if (IS_ERR(phy_provider)) {
> + dev_err(dev, "failed to register PHY provider\n");
> + return PTR_ERR(phy_provider);
> + }
> +
> + phy = devm_phy_create(dev, &simple_phy_ops, NULL);
> + if (IS_ERR(phy)) {
> + dev_err(dev, "failed to create PHY\n");
> + return PTR_ERR(phy);
> + }
> +
> + sphy->mask = 1;
> + sphy->on_value = ~0;
> + sphy->off_value = 0;
> +
> + of_property_read_u32(dev->of_node, "mask", &sphy->mask);
This means your driver will depend on dt data to describe how the register
should look like. Not a good idea.
> + of_property_read_u32(dev->of_node, "on-value", &sphy->on_value);
> + of_property_read_u32(dev->of_node, "off-value", &sphy->off_value);
> +
> + phy_set_drvdata(phy, sphy);
> +
> + dev_info(dev, "probe successful\n");
Lets not make the boot noisy.
Thanks
Kishon
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[RFC 04/12] phy: Add simple-phy driver
Add simple-phy driver to support a single register
PHY interfaces present on Exynos4 SoC.
Signed-off-by: Tomasz Stanislawski
---
drivers/phy/Kconfig |5 ++
drivers/phy/Makefile |1 +
drivers/phy/phy-simple.c | 128 ++
3 files changed, 134 insertions(+)
create mode 100644 drivers/phy/phy-simple.c
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index ac239ac..619c657 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -38,4 +38,9 @@ config TWL4030_USB
This transceiver supports high and full speed devices plus,
in host mode, low speed.
+config PHY_SIMPLE
+ tristate "Simple PHY driver"
+ help
+ Support for PHY controllers configured using single register.
+
endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 0dd8a98..3d68e19 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -5,3 +5,4 @@
obj-$(CONFIG_GENERIC_PHY) += phy-core.o
obj-$(CONFIG_OMAP_USB2)+= phy-omap-usb2.o
obj-$(CONFIG_TWL4030_USB) += phy-twl4030-usb.o
+obj-$(CONFIG_PHY_SIMPLE) += phy-simple.o
diff --git a/drivers/phy/phy-simple.c b/drivers/phy/phy-simple.c
new file mode 100644
index 000..4a28af7
--- /dev/null
+++ b/drivers/phy/phy-simple.c
@@ -0,0 +1,128 @@
+/*
+ * Simple PHY driver
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ * Author: Tomasz Stanislawski
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+struct simple_phy {
+ spinlock_t slock;
+ u32 on_value;
+ u32 off_value;
+ u32 mask;
+ void __iomem *regs;
+};
+
+static int sphy_set(struct simple_phy *sphy, bool on)
+{
+ u32 reg;
+
+ spin_lock(&sphy->slock);
+
+ reg = readl(sphy->regs);
+ reg &= ~sphy->mask;
+ reg |= sphy->mask & (on ? sphy->on_value : sphy->off_value);
+ writel(reg, sphy->regs);
+
+ spin_unlock(&sphy->slock);
+
+ return 0;
+}
+
+static int simple_phy_power_on(struct phy *phy)
+{
+ return sphy_set(phy_get_drvdata(phy), 1);
+}
+
+static int simple_phy_power_off(struct phy *phy)
+{
+ return sphy_set(phy_get_drvdata(phy), 0);
+}
+
+static struct phy_ops simple_phy_ops = {
+ .power_on = simple_phy_power_on,
+ .power_off = simple_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int simple_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct simple_phy *sphy;
+ struct resource *res;
+ struct phy_provider *phy_provider;
+ struct phy *phy;
+
+ sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
+ if (!sphy)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ sphy->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(sphy->regs)) {
+ dev_err(dev, "failed to ioremap registers\n");
+ return PTR_ERR(sphy->regs);
+ }
+
+ spin_lock_init(&sphy->slock);
+
+ phy_provider = devm_of_phy_provider_register(dev, NULL);
+ if (IS_ERR(phy_provider)) {
+ dev_err(dev, "failed to register PHY provider\n");
+ return PTR_ERR(phy_provider);
+ }
+
+ phy = devm_phy_create(dev, &simple_phy_ops, NULL);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create PHY\n");
+ return PTR_ERR(phy);
+ }
+
+ sphy->mask = 1;
+ sphy->on_value = ~0;
+ sphy->off_value = 0;
+
+ of_property_read_u32(dev->of_node, "mask", &sphy->mask);
+ of_property_read_u32(dev->of_node, "on-value", &sphy->on_value);
+ of_property_read_u32(dev->of_node, "off-value", &sphy->off_value);
+
+ phy_set_drvdata(phy, sphy);
+
+ dev_info(dev, "probe successful\n");
+
+ return 0;
+}
+
+static const struct of_device_id simple_phy_of_match[] = {
+ { .compatible = "simple-phy" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, simple_phy_of_match);
+
+static struct platform_driver simple_phy_driver = {
+ .probe = simple_phy_probe,
+ .driver = {
+ .of_match_table = simple_phy_of_match,
+ .name = "simple-phy",
+ .owner = THIS_MODULE,
+ }
+};
+module_platform_driver(simple_phy_driver);
+
+MODULE_DESCRIPTION("Simple PHY driver");
+MODULE_AUTHOR("Tomasz Stanislawski ");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5
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