Hi Arnd,
On Wed, Aug 1, 2012 at 8:50 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> On Wednesday 01 August 2012, Praveen Paneri wrote:
>> This patch set introduces a phy driver for samsung SoCs. It uses the existing
>> transceiver infrastructure to provide phy control functions. Use of this driver
>> can be extended for usb host phy as well. Over the period of time all the phy
>> related code for most of the samsung SoCs can be integrated here.
>> Removing the existing phy code from mach-s3c64xx but not from other machine
>> code.This driver is tested with smdk6410 and Exynos4210(with DT).
>
> This looks very nice overall, great work!
Thank you!
>
> We will still have to take care of the pmu isolation callback in the
> long run, when we get to the point of removing all auxdata. Do you
> have a plan on how to do that? If yes, it would be good to mention
> that in the changelog.
Yes! I understand this problem and this is the reason these patches
were sitting in my system for couple of weeks. In a discussion with
Thomas an idea of using the existing regulator framework to
enable/disable numerous PHYs came up. For example the PMU unit
of Exynos4210 has a register set dedicated just to control USBD_PHY,
HDMI_PHY, MIPI_PHY, DAC_PHY and more. If a regulator with
each phy control register as LDO is written, the phy driver becomes a
static consumer and will modify as below.
diff --git a/drivers/usb/phy/sec_usbphy.c b/drivers/usb/phy/sec_usbphy.c
index 33119eb..4f69675 100644
--- a/drivers/usb/phy/sec_usbphy.c
+++ b/drivers/usb/phy/sec_usbphy.c
@@ -28,8 +28,8 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
+#include <linux/regulator/consumer.h>
#include <linux/usb/otg.h>
-#include <linux/platform_data/s3c-hsotg.h>
#include "sec_usbphy.h"
@@ -41,7 +41,7 @@ enum sec_cpu_type {
/*
* struct sec_usbphy - transceiver driver state
* @phy: transceiver structure
- * @plat: platform data
+ * @vusbphy: PMU regulator for usb phy
* @dev: The parent device supplied to the probe function
* @clk: usb phy clock
* @regs: usb phy register memory base
@@ -49,7 +49,7 @@ enum sec_cpu_type {
*/
struct sec_usbphy {
struct usb_phy phy;
- struct s3c_usbphy_plat *plat;
+ struct regulator *vusbphy;
struct device *dev;
struct clk *clk;
void __iomem *regs;
@@ -187,8 +187,11 @@ static int sec_usbphy_init(struct usb_phy *phy)
}
/* Disable phy isolation */
- if (sec->plat && sec->plat->pmu_isolation)
- sec->plat->pmu_isolation(false);
+ ret = regulator_enable(sec->vusbphy);
+ if (ret) {
+ dev_err(sec->dev, "Failed to enable regulator for USBPHY\n");
+ return ret;
+ }
/* Initialize usb phy registers */
sec_usbphy_enable(sec);
@@ -208,8 +211,8 @@ static void sec_usbphy_shutdown(struct usb_phy *phy)
sec_usbphy_disable(sec);
/* Enable phy isolation */
- if (sec->plat && sec->plat->pmu_isolation)
- sec->plat->pmu_isolation(true);
+ if (regulator_disable(sec->vusbphy))
+ dev_err(sec->dev, "Failed to disable regulator for USBPHY\n");
/* Disable the phy clock */
sec_usbphy_clk_control(sec, false);
@@ -263,7 +266,6 @@ static int __devinit sec_usbphy_probe(struct
platform_device *pdev)
return -ENOMEM;
sec->dev = &pdev->dev;
- sec->plat = pdata;
sec->regs = phy_base;
sec->phy.dev = sec->dev;
sec->phy.label = "sec-usbphy";
@@ -271,6 +273,14 @@ static int __devinit sec_usbphy_probe(struct
platform_device *pdev)
sec->phy.shutdown = sec_usbphy_shutdown;
sec->cpu_type = sec_usbphy_get_driver_data(pdev);
+ /* acquire regulator */
+ sec->vusbphy = regulator_get(sec->dev, "usbdphy");
+ if (IS_ERR_OR_NULL(sec->vusbphy)) {
+ dev_err(dev, "failed to get regulator 'usbdphy'\n");
+ ret = -ENXIO;
+ goto err;
+ }
+
ret = usb_add_phy(&sec->phy, USB_PHY_TYPE_USB2);
if (ret)
goto err;
@@ -292,6 +302,7 @@ static int __exit sec_usbphy_remove(struct
platform_device *pdev)
clk_put(sec->clk);
sec->clk = NULL;
}
+ regulator_put(sec->vusbphy);
return 0;
}
This kind of regulator, if generalised can be useful.
Please comment.
>
> My guess is that the PMU code should be moved into a higher-level
> abstraction. I don't know if you would use one of those we already
Could you please point out the location of the code.
> have or whether you'd introduce a new subsystem for those. Apparently.
Havent thought about it. Trying to work it out with the existing infra of the
kernel.
> other platforms have similar issues, so I'd suggest you leave the
> callback for now, but we should at some point discuss what to to
> about it.
>
> Arnd
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Praveen
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