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Commit ed8f8318 authored by Peter Chen's avatar Peter Chen Committed by Greg Kroah-Hartman
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usb: chipidea: add freescale imx28 special write register method 

According to Freescale imx28 Errata, "ENGR119653 USB: ARM to USB
register error issue", All USB register write operations must
use the ARM SWP instruction. So, we implement special hw_write
and hw_test_and_clear for imx28.

Discussion for it at below:
http://marc.info/?l=linux-usb&m=137996395529294&w=2



This patch is needed for stable tree 3.11+.

Cc: stable@vger.kernel.org
Cc: robert.hodaszi@digi.com
Signed-off-by: default avatarPeter Chen <peter.chen@freescale.com>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Tested-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent feffe09f

drivers/usb/chipidea/ci.h

+24 −2
Original line number Diff line number Diff line
@@ -164,6 +164,7 @@ struct hw_bank { 
 * @id_event: indicates there is an id event, and handled at ci_otg_work

 * @b_sess_valid_event: indicates there is a vbus event, and handled

 * at ci_otg_work

 * @imx28_write_fix: Freescale imx28 needs swp instruction for writing

 */

struct ci_hdrc {

	struct device			*dev;
@@ -202,6 +203,7 @@ struct ci_hdrc { 
	struct dentry			*debugfs;

	bool				id_event;

	bool				b_sess_valid_event;

	bool				imx28_write_fix;

};



static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)
@@ -250,6 +252,26 @@ static inline u32 hw_read(struct ci_hdrc *ci, enum ci_hw_regs reg, u32 mask) 
	return ioread32(ci->hw_bank.regmap[reg]) & mask;

}



#ifdef CONFIG_SOC_IMX28

static inline void imx28_ci_writel(u32 val, volatile void __iomem *addr)

{

	__asm__ ("swp %0, %0, [%1]" : : "r"(val), "r"(addr));

}

#else

static inline void imx28_ci_writel(u32 val, volatile void __iomem *addr)

{

}

#endif



static inline void __hw_write(struct ci_hdrc *ci, u32 val,

		void __iomem *addr)

{

	if (ci->imx28_write_fix)

		imx28_ci_writel(val, addr);

	else

		iowrite32(val, addr);

}



/**

 * hw_write: writes to a hw register

 * @reg:  register index
@@ -263,7 +285,7 @@ static inline void hw_write(struct ci_hdrc *ci, enum ci_hw_regs reg, 
		data = (ioread32(ci->hw_bank.regmap[reg]) & ~mask)

			| (data & mask);



	iowrite32(data, ci->hw_bank.regmap[reg]);

	__hw_write(ci, data, ci->hw_bank.regmap[reg]);

}



/**
@@ -278,7 +300,7 @@ static inline u32 hw_test_and_clear(struct ci_hdrc *ci, enum ci_hw_regs reg, 
{

	u32 val = ioread32(ci->hw_bank.regmap[reg]) & mask;



	iowrite32(val, ci->hw_bank.regmap[reg]);

	__hw_write(ci, val, ci->hw_bank.regmap[reg]);

	return val;

}

drivers/usb/chipidea/core.c

+2 −0
Original line number Diff line number Diff line
@@ -548,6 +548,8 @@ static int ci_hdrc_probe(struct platform_device *pdev) 


	ci->dev = dev;

	ci->platdata = dev->platform_data;

	ci->imx28_write_fix = !!(ci->platdata->flags &

		CI_HDRC_IMX28_WRITE_FIX);



	ret = hw_device_init(ci, base);

	if (ret < 0) {

drivers/usb/chipidea/host.c

+1 −0
Original line number Diff line number Diff line
@@ -65,6 +65,7 @@ static int host_start(struct ci_hdrc *ci) 
	ehci->caps = ci->hw_bank.cap;

	ehci->has_hostpc = ci->hw_bank.lpm;

	ehci->has_tdi_phy_lpm = ci->hw_bank.lpm;

	ehci->imx28_write_fix = ci->imx28_write_fix;



	if (ci->platdata->reg_vbus) {

		ret = regulator_enable(ci->platdata->reg_vbus);

include/linux/usb/chipidea.h

+1 −0
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ struct ci_hdrc_platform_data { 
	 * but otg is not supported (no register otgsc).

	 */

#define CI_HDRC_DUAL_ROLE_NOT_OTG	BIT(4)

#define CI_HDRC_IMX28_WRITE_FIX		BIT(5)

	enum usb_dr_mode	dr_mode;

#define CI_HDRC_CONTROLLER_RESET_EVENT		0

#define CI_HDRC_CONTROLLER_STOPPED_EVENT	1