[PATCH v2 2/2] phy: add a driver for the Rockchip SoC internal eMMC PHY
Kishon Vijay Abraham I
kishon at ti.com
Tue Feb 2 22:39:35 PST 2016
Hi,
On Tuesday 05 January 2016 06:38 AM, Shawn Lin wrote:
> This patch to add a generic PHY driver for ROCKCHIP eMMC PHY.
> Access the PHY via registers provided by GRF (general register
> files) module.
>
> Signed-off-by: Shawn Lin <shawn.lin at rock-chips.com>
>
> ---
>
> Changes in v2:
> - remove phy from rockchip_emmc_phy
> - remove state from rockchip_emmc_phy
> - remove on/off from init/exit
>
> drivers/phy/Kconfig | 7 ++
> drivers/phy/Makefile | 1 +
> drivers/phy/phy-rockchip-emmc.c | 241 ++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 249 insertions(+)
> create mode 100644 drivers/phy/phy-rockchip-emmc.c
>
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 03cb3ea..47d16e3 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -320,6 +320,13 @@ config PHY_ROCKCHIP_USB
> help
> Enable this to support the Rockchip USB 2.0 PHY.
>
> +config PHY_ROCKCHIP_EMMC
> + tristate "Rockchip EMMC PHY Driver"
> + depends on ARCH_ROCKCHIP && OF
> + select GENERIC_PHY
> + help
> + Enable this to support the Rockchip EMMC PHY.
> +
> config PHY_ST_SPEAR1310_MIPHY
> tristate "ST SPEAR1310-MIPHY driver"
> select GENERIC_PHY
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 075db1a..ed8f175 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -35,6 +35,7 @@ phy-exynos-usb2-$(CONFIG_PHY_S5PV210_USB2) += phy-s5pv210-usb2.o
> obj-$(CONFIG_PHY_EXYNOS5_USBDRD) += phy-exynos5-usbdrd.o
> obj-$(CONFIG_PHY_QCOM_APQ8064_SATA) += phy-qcom-apq8064-sata.o
> obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o
> +obj-$(CONFIG_PHY_ROCKCHIP_EMMC) += phy-rockchip-emmc.o
> obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA) += phy-qcom-ipq806x-sata.o
> obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY) += phy-spear1310-miphy.o
> obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY) += phy-spear1340-miphy.o
> diff --git a/drivers/phy/phy-rockchip-emmc.c b/drivers/phy/phy-rockchip-emmc.c
> new file mode 100644
> index 0000000..6a157c2
> --- /dev/null
> +++ b/drivers/phy/phy-rockchip-emmc.c
> @@ -0,0 +1,241 @@
> +/*
> + * Rockchip emmc PHY driver
> + *
> + * Copyright (C) 2015 Shawn Lin <shawn.lin at rock-chips.com>
> + * Copyright (C) 2015 ROCKCHIP, Inc.
2016?
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +
> +/*
> + * The higher 16-bit of this register is used for write protection
> + * only if BIT(x + 16) set to 1 the BIT(x) can be written.
> + */
> +#define HIWORD_UPDATE(val, mask, shift) \
> + ((val) << (shift) | (mask) << ((shift) + 16))
> +
> +/* Register definition */
> +#define GRF_EMMCPHY_CON0 0x0
> +#define GRF_EMMCPHY_CON1 0x4
> +#define GRF_EMMCPHY_CON2 0x8
> +#define GRF_EMMCPHY_CON3 0xc
> +#define GRF_EMMCPHY_CON4 0x10
> +#define GRF_EMMCPHY_CON5 0x14
> +#define GRF_EMMCPHY_CON6 0x18
> +#define GRF_EMMCPHY_STATUS 0x20
> +
> +#define PHYCTRL_PDB_MASK 0x1
> +#define PHYCTRL_PDB_SHIFT 0x0
> +#define PHYCTRL_PDB_PWR_ON 0x1
> +#define PHYCTRL_PDB_PWR_OFF 0x0
> +#define PHYCTRL_ENDLL_MASK 0x1
> +#define PHYCTRL_ENDLL_SHIFT 0x1
> +#define PHYCTRL_ENDLL_ENABLE 0x1
> +#define PHYCTRL_ENDLL_DISABLE 0x0
> +#define PHYCTRL_CALDONE_MASK 0x1
> +#define PHYCTRL_CALDONE_SHIFT 0x6
> +#define PHYCTRL_CALDONE_DONE 0x1
> +#define PHYCTRL_CALDONE_GOING 0x0
> +#define PHYCTRL_DLLRDY_MASK 0x1
> +#define PHYCTRL_DLLRDY_SHIFT 0x5
> +#define PHYCTRL_DLLRDY_DONE 0x1
> +#define PHYCTRL_DLLRDY_GOING 0x0
> +
> +struct rockchip_emmc_phy {
> + unsigned int reg_offset;
> + struct regmap *reg_base;
> +};
> +
> +static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
> + bool on_off)
> +{
> + unsigned int caldone;
> + unsigned int dllrdy;
> +
> + /*
> + * Keep phyctrl_pdb and phyctrl_endll low to allow
> + * initialization of CALIO state M/C DFFs
> + */
> + regmap_write(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_CON6,
> + HIWORD_UPDATE(PHYCTRL_PDB_PWR_OFF,
> + PHYCTRL_PDB_MASK,
> + PHYCTRL_PDB_SHIFT));
> + regmap_write(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_CON6,
> + HIWORD_UPDATE(PHYCTRL_ENDLL_DISABLE,
> + PHYCTRL_ENDLL_MASK,
> + PHYCTRL_ENDLL_SHIFT));
> +
> + /* Already finish power_off above */
> + if (on_off == PHYCTRL_PDB_PWR_OFF)
> + return 0;
> +
> + /*
> + * According to the user manual, calpad calibration
> + * cycle takes more than 2us without the minimal recommended
> + * value, so we may need a little margin here
> + */
> + udelay(3);
> + regmap_write(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_CON6,
> + HIWORD_UPDATE(PHYCTRL_PDB_PWR_ON,
> + PHYCTRL_PDB_MASK,
> + PHYCTRL_PDB_SHIFT));
> +
> + /*
> + * According to the user manual, it asks driver to
> + * wait 5us for calpad busy trimming
> + */
> + udelay(5);
> + regmap_read(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
> + &caldone);
> + caldone = (caldone >> PHYCTRL_CALDONE_SHIFT) & PHYCTRL_CALDONE_MASK;
> + if (caldone != PHYCTRL_CALDONE_DONE) {
> + pr_err("rockchip_emmc_phy_power: caldone timeout.\n");
> + return -ETIMEDOUT;
> + }
> +
> + /*
> + * Enable analog DLL circuits, and we need extra 10.2us
> + * for dll to be ready for work.
> + */
> + regmap_write(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_CON6,
> + HIWORD_UPDATE(PHYCTRL_ENDLL_ENABLE,
> + PHYCTRL_ENDLL_MASK,
> + PHYCTRL_ENDLL_SHIFT));
> + udelay(11);
add a comment for this delay too.
> + regmap_read(rk_phy->reg_base,
> + rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
> + &dllrdy);
> + dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
> + if (dllrdy != PHYCTRL_DLLRDY_DONE) {
> + pr_err("rockchip_emmc_phy_power: dllrdy timeout.\n");
> + return -ETIMEDOUT;
> + }
> +
> + return 0;
> +}
> +
> +static int rockchip_emmc_phy_power_off(struct phy *phy)
> +{
> + struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
> + int ret = 0;
> +
> + /* Power down emmc phy analog blocks */
> + ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int rockchip_emmc_phy_power_on(struct phy *phy)
> +{
> + struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
> + int ret = 0;
> +
> + /* Power up emmc phy analog blocks */
> + ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON);
> + if (ret)
> + return ret;
> +
> + return 0;
> +}
> +
> +static int rockchip_emmc_phy_init(struct phy *phy)
> +{
> + return 0;
> +}
> +
> +static int rockchip_emmc_phy_exit(struct phy *phy)
> +{
> + return 0;
> +}
empty init/exit functions are not required.
Thanks
Kishon
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