[PATCH v6 resend 5/5] phy: freescale: phy-fsl-imx8-mipi-dphy: Add i.MX8qxp LVDS PHY mode support
Vinod Koul
vkoul at kernel.org
Tue Apr 12 23:21:33 PDT 2022
On 02-04-22, 13:24, Liu Ying wrote:
> i.MX8qxp SoC embeds a Mixel MIPI DPHY + LVDS PHY combo which supports
> either a MIPI DSI display or a LVDS display. The PHY mode is controlled
> by SCU firmware and the driver would call a SCU firmware function to
> configure the PHY mode. The single LVDS PHY has 4 data lanes to support
> a LVDS display. Also, with a master LVDS PHY and a slave LVDS PHY, they
> may work together to support a LVDS display with 8 data lanes(usually, dual
> LVDS link display). Note that this patch supports the LVDS PHY mode only
> for the i.MX8qxp Mixel combo PHY, i.e., the MIPI DPHY mode is yet to be
> supported, so for now error would be returned from ->set_mode() if MIPI
> DPHY mode is passed over to it for the combo PHY.
>
> Cc: Guido Günther <agx at sigxcpu.org>
> Cc: Robert Chiras <robert.chiras at nxp.com>
> Cc: Kishon Vijay Abraham I <kishon at ti.com>
> Cc: Vinod Koul <vkoul at kernel.org>
> Cc: Shawn Guo <shawnguo at kernel.org>
> Cc: Sascha Hauer <s.hauer at pengutronix.de>
> Cc: Pengutronix Kernel Team <kernel at pengutronix.de>
> Cc: Fabio Estevam <festevam at gmail.com>
> Cc: NXP Linux Team <linux-imx at nxp.com>
> Reviewed-by: Guido Günther <agx at sigxcpu.org>
> Signed-off-by: Liu Ying <victor.liu at nxp.com>
> ---
> v5->v6:
> * No change.
>
> v4->v5:
> * No change.
>
> v3->v4:
> * Add Guido's R-b tag.
>
> v2->v3:
> * Improve readability of mixel_dphy_set_mode(). (Guido)
>
> v1->v2:
> * Print invalid PHY mode in dmesg. (Guido)
>
> .../phy/freescale/phy-fsl-imx8-mipi-dphy.c | 269 +++++++++++++++++-
> 1 file changed, 258 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> index a95572b397ca..af1ecda091c7 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> @@ -4,17 +4,31 @@
> * Copyright 2019 Purism SPC
> */
>
> +#include <linux/bitfield.h>
> #include <linux/clk.h>
> #include <linux/clk-provider.h>
> #include <linux/delay.h>
> +#include <linux/firmware/imx/ipc.h>
> +#include <linux/firmware/imx/svc/misc.h>
> #include <linux/io.h>
> #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_platform.h>
> #include <linux/phy/phy.h>
> #include <linux/platform_device.h>
> #include <linux/regmap.h>
> +#include <dt-bindings/firmware/imx/rsrc.h>
> +
> +/* Control and Status Registers(CSR) */
> +#define PHY_CTRL 0x00
> +#define CCM_MASK GENMASK(7, 5)
> +#define CCM(n) FIELD_PREP(CCM_MASK, (n))
> +#define CA_MASK GENMASK(4, 2)
> +#define CA(n) FIELD_PREP(CA_MASK, (n))
> +#define RFB BIT(1)
> +#define LVDS_EN BIT(0)
>
> /* DPHY registers */
> #define DPHY_PD_DPHY 0x00
> @@ -55,8 +69,15 @@
> #define PWR_ON 0
> #define PWR_OFF 1
>
> +#define MIN_VCO_FREQ 640000000
> +#define MAX_VCO_FREQ 1500000000
> +
> +#define MIN_LVDS_REFCLK_FREQ 24000000
> +#define MAX_LVDS_REFCLK_FREQ 150000000
> +
> enum mixel_dphy_devtype {
> MIXEL_IMX8MQ,
> + MIXEL_IMX8QXP,
> };
>
> struct mixel_dphy_devdata {
> @@ -65,6 +86,7 @@ struct mixel_dphy_devdata {
> u8 reg_rxlprp;
> u8 reg_rxcdrp;
> u8 reg_rxhs_settle;
> + bool is_combo; /* MIPI DPHY and LVDS PHY combo */
> };
>
> static const struct mixel_dphy_devdata mixel_dphy_devdata[] = {
> @@ -74,6 +96,10 @@ static const struct mixel_dphy_devdata mixel_dphy_devdata[] = {
> .reg_rxlprp = 0x40,
> .reg_rxcdrp = 0x44,
> .reg_rxhs_settle = 0x48,
> + .is_combo = false,
> + },
> + [MIXEL_IMX8QXP] = {
> + .is_combo = true,
> },
> };
>
> @@ -95,8 +121,12 @@ struct mixel_dphy_cfg {
> struct mixel_dphy_priv {
> struct mixel_dphy_cfg cfg;
> struct regmap *regmap;
> + struct regmap *lvds_regmap;
> struct clk *phy_ref_clk;
> const struct mixel_dphy_devdata *devdata;
> + struct imx_sc_ipc *ipc_handle;
> + bool is_slave;
> + int id;
> };
>
> static const struct regmap_config mixel_dphy_regmap_config = {
> @@ -317,7 +347,8 @@ static int mixel_dphy_set_pll_params(struct phy *phy)
> return 0;
> }
>
> -static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> +static int
> +mixel_dphy_configure_mipi_dphy(struct phy *phy, union phy_configure_opts *opts)
Please dont change things like this.. A patch should do only one thing :)
> {
> struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> struct mixel_dphy_cfg cfg = { 0 };
> @@ -345,15 +376,121 @@ static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> return 0;
> }
>
> +static int
> +mixel_dphy_configure_lvds_phy(struct phy *phy, union phy_configure_opts *opts)
> +{
> + struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> + struct phy_configure_opts_lvds *lvds_opts = &opts->lvds;
> + unsigned long data_rate;
> + unsigned long fvco;
> + u32 rsc;
> + u32 co;
> + int ret;
> +
> + priv->is_slave = lvds_opts->is_slave;
I think you should check if lvds_opts is valid before dereferencing it..
> +
> + /* LVDS interface pins */
> + regmap_write(priv->lvds_regmap, PHY_CTRL, CCM(0x5) | CA(0x4) | RFB);
can we avoid magic numbers?
> +
> + /* enable MODE8 only for slave LVDS PHY */
> + rsc = priv->id ? IMX_SC_R_MIPI_1 : IMX_SC_R_MIPI_0;
> + ret = imx_sc_misc_set_control(priv->ipc_handle, rsc, IMX_SC_C_DUAL_MODE,
> + lvds_opts->is_slave);
> + if (ret) {
> + dev_err(&phy->dev, "Failed to configure MODE8: %d\n", ret);
> + return ret;
> + }
> +
> + /*
> + * Choose an appropriate divider ratio to meet the requirement of
> + * PLL VCO frequency range.
> + *
> + * ----- 640MHz ~ 1500MHz ------------ ---------------
> + * | VCO | ----------------> | CO divider | -> | LVDS data rate|
> + * ----- FVCO ------------ ---------------
> + * 1/2/4/8 div 7 * differential_clk_rate
> + */
> + data_rate = 7 * lvds_opts->differential_clk_rate;
> + for (co = 1; co <= 8; co *= 2) {
> + fvco = data_rate * co;
> +
> + if (fvco >= MIN_VCO_FREQ)
> + break;
> + }
> +
> + if (fvco < MIN_VCO_FREQ || fvco > MAX_VCO_FREQ) {
> + dev_err(&phy->dev, "VCO frequency %lu is out of range\n", fvco);
> + return -ERANGE;
> + }
> +
> + /*
> + * CO is configurable, while CN and CM are not,
> + * as fixed ratios 1 and 7 are applied respectively.
> + */
> + phy_write(phy, __ffs(co), DPHY_CO);
> +
> + /* set reference clock rate */
> + clk_set_rate(priv->phy_ref_clk, lvds_opts->differential_clk_rate);
> +
> + return ret;
> +}
> +
> +static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts *opts)
> +{
> + if (phy->attrs.mode == PHY_MODE_MIPI_DPHY)
> + return mixel_dphy_configure_mipi_dphy(phy, opts);
> + else if (phy->attrs.mode == PHY_MODE_LVDS)
> + return mixel_dphy_configure_lvds_phy(phy, opts);
> +
> + dev_err(&phy->dev,
> + "Failed to configure PHY with invalid PHY mode: %d\n",
> + phy->attrs.mode);
single line for this please
> + return -EINVAL;
> +}
> +
> +static int
> +mixel_dphy_validate_lvds_phy(struct phy *phy, union phy_configure_opts *opts)
> +{
> + struct phy_configure_opts_lvds *lvds_cfg = &opts->lvds;
> +
> + if (lvds_cfg->bits_per_lane_and_dclk_cycle != 7) {
> + dev_err(&phy->dev, "Invalid bits per LVDS data lane: %u\n",
> + lvds_cfg->bits_per_lane_and_dclk_cycle);
> + return -EINVAL;
> + }
> +
> + if (lvds_cfg->lanes != 4) {
> + dev_err(&phy->dev, "Invalid LVDS data lanes: %u\n",
> + lvds_cfg->lanes);
here too, make it better read
> + return -EINVAL;
> + }
> +
> + if (lvds_cfg->differential_clk_rate < MIN_LVDS_REFCLK_FREQ ||
> + lvds_cfg->differential_clk_rate > MAX_LVDS_REFCLK_FREQ) {
> + dev_err(&phy->dev,
> + "Invalid LVDS differential clock rate: %lu\n",
> + lvds_cfg->differential_clk_rate);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> static int mixel_dphy_validate(struct phy *phy, enum phy_mode mode, int submode,
> union phy_configure_opts *opts)
> {
> - struct mixel_dphy_cfg cfg = { 0 };
> + if (mode == PHY_MODE_MIPI_DPHY) {
> + struct mixel_dphy_cfg mipi_dphy_cfg = { 0 };
>
> - if (mode != PHY_MODE_MIPI_DPHY)
> - return -EINVAL;
> + return mixel_dphy_config_from_opts(phy, &opts->mipi_dphy,
> + &mipi_dphy_cfg);
the line should be justified to previos line open brace (checkpatch
--strict will warn you about this style miss)
--
~Vinod
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