[PATCH 2/2] phy: mediatek: phy-mtk-tphy: support USB2UART switch

Chunfeng Yun chunfeng.yun at mediatek.com
Tue Jul 27 18:55:14 PDT 2021


On Tue, 2021-07-27 at 18:50 +0800, Macpaul Lin wrote:
> Some embedded platform shared PINs between USB and UART.
> For example, some phone will use special cable detection in boot loader
> to switch USB port function into UART mode.
> 
> This patch support USB2UART switch function in phy-mtk-tphy.
> 1. Implement USB2UART switch API support in phy-mtk-tphy.
> 2. Use PHY_MODE_UART support according to new mode in phy.h.
> 3. Use mtk_phy_get_mode_ext() to query the current MODE from hardware.
> 
> Signed-off-by: Macpaul Lin <macpaul.lin at mediatek.com>
> ---
>  drivers/phy/mediatek/phy-mtk-tphy.c |  114 +++++++++++++++++++++++++++++++++++
>  1 file changed, 114 insertions(+)
> 
title: please use "phy: phy-mtk-tphy: ..."  as other patches


> diff --git a/drivers/phy/mediatek/phy-mtk-tphy.c b/drivers/phy/mediatek/phy-mtk-tphy.c
> index cdbcc49..a7dfeec 100644
> --- a/drivers/phy/mediatek/phy-mtk-tphy.c
> +++ b/drivers/phy/mediatek/phy-mtk-tphy.c
> @@ -68,6 +68,7 @@
>  #define PA6_RG_U2_SQTH_VAL(x)	(0xf & (x))
>  
>  #define U3P_U2PHYACR4		0x020
> +#define P2C_RG_USB20_DM_100K_EN		BIT(17)
>  #define P2C_RG_USB20_GPIO_CTL		BIT(9)
>  #define P2C_USB20_GPIO_MODE		BIT(8)
>  #define P2C_U2_GPIO_CTR_MSK	(P2C_RG_USB20_GPIO_CTL | P2C_USB20_GPIO_MODE)
> @@ -76,6 +77,12 @@
>  #define P2C_RG_SIF_U2PLL_FORCE_ON	BIT(24)
>  
>  #define U3P_U2PHYDTM0		0x068
> +#define P2C_RG_UART_MODE		GENMASK(31, 30)
> +#define P2C_RG_UART_MODE_VAL(x)		((0x3 & (x)) << 30)
> +#define P2C_RG_UART_MODE_OFET		(30)
> +#define P2C_FORCE_UART_I		BIT(29)
> +#define P2C_FORCE_UART_BIAS_EN		BIT(28)
> +#define P2C_FORCE_UART_TX_OE		BIT(27)
>  #define P2C_FORCE_UART_EN		BIT(26)
>  #define P2C_FORCE_DATAIN		BIT(23)
>  #define P2C_FORCE_DM_PULLDOWN		BIT(21)
> @@ -98,6 +105,8 @@
>  		P2C_RG_DPPULLDOWN | P2C_RG_TERMSEL)
>  
>  #define U3P_U2PHYDTM1		0x06C
> +#define P2C_RG_UART_BIAS_EN		BIT(18)
> +#define P2C_RG_UART_TX_OE		BIT(17)
>  #define P2C_RG_UART_EN			BIT(16)
>  #define P2C_FORCE_IDDIG		BIT(9)
>  #define P2C_RG_VBUSVALID		BIT(5)
> @@ -600,6 +609,90 @@ static void u2_phy_instance_exit(struct mtk_tphy *tphy,
>  	}
>  }
>  
> +static void u2_phy_instance_set_mode_2uart(struct u2phy_banks *u2_banks)
> +{
> +	u32 tmp;
> +
> +	/* Clear PA6_RG_U2_BC11_SW_EN */
remove the comments
> +	tmp = readl(u2_banks->com + U3P_USBPHYACR6);
> +	tmp &= ~(PA6_RG_U2_BC11_SW_EN);
> +	writel(tmp, u2_banks->com + U3P_USBPHYACR6);
> +
> +	/* Set P2C_RG_SUSPENDM */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_RG_SUSPENDM;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_FORCE_SUSPENDM */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_FORCE_SUSPENDM;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Clear and Set P2C_RG_UART_MODE to 2'b01 */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp &= ~(P2C_RG_UART_MODE);
> +	tmp |= P2C_RG_UART_MODE_VAL(0x1);
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Clear P2C_FORCE_UART_I */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp &= ~(P2C_FORCE_UART_I);
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_FORCE_UART_BIAS_EN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_FORCE_UART_BIAS_EN;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_FORCE_UART_TX_OE */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_FORCE_UART_TX_OE;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_FORCE_UART_EN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_FORCE_UART_EN;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_RG_UART_BIAS_EN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_RG_UART_BIAS_EN;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_RG_UART_TX_OE */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_RG_UART_TX_OE;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_RG_UART_EN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp |= P2C_RG_UART_EN;
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +
> +	/* Set P2C_RG_USB20_DM_100K_EN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYACR4);
> +	tmp |= P2C_RG_USB20_DM_100K_EN;
> +	writel(tmp, u2_banks->com + U3P_U2PHYACR4);
> +
> +	/* Clear P2C_RG_DMPULLDOWN, P2C_RG_DPPULLDOWN */
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +	tmp &= ~(P2C_RG_DPPULLDOWN | P2C_RG_DMPULLDOWN);
> +	writel(tmp, u2_banks->com + U3P_U2PHYDTM0);
> +}
> +
> +static int u2_phy_instance_get_mode_ext(struct mtk_tphy *tphy, struct mtk_phy_instance *instance)
> +{
> +	struct u2phy_banks *u2_banks = &instance->u2_banks;
> +	u32 tmp;
> +
> +	tmp = readl(u2_banks->com + U3P_U2PHYDTM0);
> +
> +	if ((tmp & P2C_RG_UART_MODE) >> P2C_RG_UART_MODE_OFET)
> +		return PHY_MODE_UART;
> +	else
> +		return PHY_MODE_USB_OTG;
> +}
> +
>  static void u2_phy_instance_set_mode(struct mtk_tphy *tphy,
>  				     struct mtk_phy_instance *instance,
>  				     enum phy_mode mode)
> @@ -609,6 +702,9 @@ static void u2_phy_instance_set_mode(struct mtk_tphy *tphy,
>  
>  	tmp = readl(u2_banks->com + U3P_U2PHYDTM1);
>  	switch (mode) {
> +	case PHY_MODE_UART:
> +		u2_phy_instance_set_mode_2uart(u2_banks);
How do you use this helper?

Can we switch back to usb phy mode if switching to uart?
When switch to uart mode, if the host supports multi-ports, it will
cause the host can't enter sleep mode anymore.

> +		return;
>  	case PHY_MODE_USB_DEVICE:
>  		tmp |= P2C_FORCE_IDDIG | P2C_RG_IDDIG;
>  		break;
> @@ -933,6 +1029,10 @@ static int mtk_phy_init(struct phy *phy)
>  		return ret;
>  	}
>  
> +	ret = u2_phy_instance_get_mode_ext(tphy, instance);
> +	if (ret == PHY_MODE_UART)
> +		return 0;
> +
>  	switch (instance->type) {
>  	case PHY_TYPE_USB2:
>  		u2_phy_instance_init(tphy, instance);
> @@ -996,6 +1096,19 @@ static int mtk_phy_exit(struct phy *phy)
>  	return 0;
>  }
>  
> +static int mtk_phy_get_mode_ext(struct phy *phy)
> +{
> +	struct mtk_phy_instance *instance = phy_get_drvdata(phy);
> +	struct mtk_tphy *tphy = dev_get_drvdata(phy->dev.parent);
> +	int ret;
> +
> +	ret = 0;
> +	if (instance->type == PHY_TYPE_USB2)
> +		ret = u2_phy_instance_get_mode_ext(tphy, instance);
> +
> +	return ret;
> +}
> +
>  static int mtk_phy_set_mode(struct phy *phy, enum phy_mode mode, int submode)
>  {
>  	struct mtk_phy_instance *instance = phy_get_drvdata(phy);
> @@ -1060,6 +1173,7 @@ static struct phy *mtk_phy_xlate(struct device *dev,
>  	.power_on	= mtk_phy_power_on,
>  	.power_off	= mtk_phy_power_off,
>  	.set_mode	= mtk_phy_set_mode,
> +	.get_mode_ext	= mtk_phy_get_mode_ext,
>  	.owner		= THIS_MODULE,
>  };
>  



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