From: Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> To: David Airlie <airlied-cv59FeDIM0c@public.gmane.org>, Daniel Vetter <daniel-/w4YWyX8dFk@public.gmane.org>, Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>, Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Maxime Ripard <maxime.ripard-LDxbnhwyfcJBDgjK7y7TUQ@public.gmane.org>, Chen-Yu Tsai <wens-jdAy2FN1RRM@public.gmane.org>, Archit Taneja <architt-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Andrzej Hajda <a.hajda-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>, Laurent Pinchart <Laurent.pinchart-ryLnwIuWjnjg/C1BVhZhaw@public.gmane.org>, Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org>, Sean Paul <seanpaul-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Cc: Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Subject: [PATCH RESEND v2 03/12] drm/bridge: extract some Analogix I2C DP common code Date: Sun, 3 Feb 2019 10:54:52 -0800 [thread overview] Message-ID: <20190203185501.8958-4-anarsoul@gmail.com> (raw) In-Reply-To: <20190203185501.8958-1-anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> From: Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org> Some code can be shared within different DP bridges by Analogix. Extract them to a new module. Signed-off-by: Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org> Signed-off-by: Vasily Khoruzhick <anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> --- drivers/gpu/drm/bridge/analogix/Kconfig | 4 + drivers/gpu/drm/bridge/analogix/Makefile | 2 + .../drm/bridge/analogix/analogix-anx78xx.c | 146 +-------------- .../drm/bridge/analogix/analogix-i2c-dptx.c | 169 ++++++++++++++++++ .../drm/bridge/analogix/analogix-i2c-dptx.h | 2 + 5 files changed, 178 insertions(+), 145 deletions(-) create mode 100644 drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig index c4d343a2f04d..ed2d05c12546 100644 --- a/drivers/gpu/drm/bridge/analogix/Kconfig +++ b/drivers/gpu/drm/bridge/analogix/Kconfig @@ -1,5 +1,6 @@ config DRM_ANALOGIX_ANX78XX tristate "Analogix ANX78XX bridge" + select DRM_ANALOGIX_DP_I2C select DRM_KMS_HELPER select REGMAP_I2C help @@ -11,3 +12,6 @@ config DRM_ANALOGIX_ANX78XX config DRM_ANALOGIX_DP tristate depends on DRM + +config DRM_ANALOGIX_DP_I2C + tristate diff --git a/drivers/gpu/drm/bridge/analogix/Makefile b/drivers/gpu/drm/bridge/analogix/Makefile index ce1687e60975..2d523b67487d 100644 --- a/drivers/gpu/drm/bridge/analogix/Makefile +++ b/drivers/gpu/drm/bridge/analogix/Makefile @@ -1,3 +1,5 @@ analogix_dp-objs := analogix_dp_core.o analogix_dp_reg.o +analogix_dp_i2c-objs := analogix-i2c-dptx.o obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix_dp.o +obj-$(CONFIG_DRM_ANALOGIX_DP_I2C) += analogix_dp_i2c.o diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c index f8433c93f463..bf8291d0ddd0 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c @@ -45,8 +45,6 @@ #define I2C_IDX_RX_P1 4 #define XTAL_CLK 270 /* 27M */ -#define AUX_CH_BUFFER_SIZE 16 -#define AUX_WAIT_TIMEOUT_MS 15 static const u8 anx78xx_i2c_addresses[] = { [I2C_IDX_TX_P0] = TX_P0, @@ -109,153 +107,11 @@ static int anx78xx_clear_bits(struct regmap *map, u8 reg, u8 mask) return regmap_update_bits(map, reg, mask, 0); } -static bool anx78xx_aux_op_finished(struct anx78xx *anx78xx) -{ - unsigned int value; - int err; - - err = regmap_read(anx78xx->map[I2C_IDX_TX_P0], SP_DP_AUX_CH_CTRL2_REG, - &value); - if (err < 0) - return false; - - return (value & SP_AUX_EN) == 0; -} - -static int anx78xx_aux_wait(struct anx78xx *anx78xx) -{ - unsigned long timeout; - unsigned int status; - int err; - - timeout = jiffies + msecs_to_jiffies(AUX_WAIT_TIMEOUT_MS) + 1; - - while (!anx78xx_aux_op_finished(anx78xx)) { - if (time_after(jiffies, timeout)) { - if (!anx78xx_aux_op_finished(anx78xx)) { - DRM_ERROR("Timed out waiting AUX to finish\n"); - return -ETIMEDOUT; - } - - break; - } - - usleep_range(1000, 2000); - } - - /* Read the AUX channel access status */ - err = regmap_read(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_CH_STATUS_REG, - &status); - if (err < 0) { - DRM_ERROR("Failed to read from AUX channel: %d\n", err); - return err; - } - - if (status & SP_AUX_STATUS) { - DRM_ERROR("Failed to wait for AUX channel (status: %02x)\n", - status); - return -ETIMEDOUT; - } - - return 0; -} - -static int anx78xx_aux_address(struct anx78xx *anx78xx, unsigned int addr) -{ - int err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_ADDR_7_0_REG, - addr & 0xff); - if (err) - return err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_ADDR_15_8_REG, - (addr & 0xff00) >> 8); - if (err) - return err; - - /* - * DP AUX CH Address Register #2, only update bits[3:0] - * [7:4] RESERVED - * [3:0] AUX_ADDR[19:16], Register control AUX CH address. - */ - err = regmap_update_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_AUX_ADDR_19_16_REG, - SP_AUX_ADDR_19_16_MASK, - (addr & 0xf0000) >> 16); - - if (err) - return err; - - return 0; -} - static ssize_t anx78xx_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct anx78xx *anx78xx = container_of(aux, struct anx78xx, aux); - u8 ctrl1 = msg->request; - u8 ctrl2 = SP_AUX_EN; - u8 *buffer = msg->buffer; - int err; - - /* The DP AUX transmit and receive buffer has 16 bytes. */ - if (WARN_ON(msg->size > AUX_CH_BUFFER_SIZE)) - return -E2BIG; - - /* Zero-sized messages specify address-only transactions. */ - if (msg->size < 1) - ctrl2 |= SP_ADDR_ONLY; - else /* For non-zero-sized set the length field. */ - ctrl1 |= (msg->size - 1) << SP_AUX_LENGTH_SHIFT; - - if ((msg->request & DP_AUX_I2C_READ) == 0) { - /* When WRITE | MOT write values to data buffer */ - err = regmap_bulk_write(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_BUF_DATA0_REG, buffer, - msg->size); - if (err) - return err; - } - - /* Write address and request */ - err = anx78xx_aux_address(anx78xx, msg->address); - if (err) - return err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_DP_AUX_CH_CTRL1_REG, - ctrl1); - if (err) - return err; - - /* Start transaction */ - err = regmap_update_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY | - SP_AUX_EN, ctrl2); - if (err) - return err; - - err = anx78xx_aux_wait(anx78xx); - if (err) - return err; - - msg->reply = DP_AUX_I2C_REPLY_ACK; - - if ((msg->size > 0) && (msg->request & DP_AUX_I2C_READ)) { - /* Read values from data buffer */ - err = regmap_bulk_read(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_BUF_DATA0_REG, buffer, - msg->size); - if (err) - return err; - } - - err = anx78xx_clear_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY); - if (err) - return err; - - return msg->size; + return anx_aux_transfer(anx78xx->map[I2C_IDX_TX_P0], msg); } static int anx78xx_set_hpd(struct anx78xx *anx78xx) diff --git a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c new file mode 100644 index 000000000000..9cb30962032e --- /dev/null +++ b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(c) 2017 Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org> + * + * Based on analogix-anx78xx.c, which is: + * Copyright(c) 2016, Analogix Semiconductor. All rights reserved. + */ + +#include <linux/module.h> +#include <linux/regmap.h> + +#include <drm/drm.h> +#include <drm/drmP.h> +#include <drm/drm_dp_helper.h> + +#include "analogix-i2c-dptx.h" + +#define AUX_WAIT_TIMEOUT_MS 15 +#define AUX_CH_BUFFER_SIZE 16 + +static int anx_clear_bits(struct regmap *map, u8 reg, u8 mask) +{ + return regmap_update_bits(map, reg, mask, 0); +} + +static bool anx_aux_op_finished(struct regmap *map_dptx) +{ + unsigned int value; + int err; + + err = regmap_read(map_dptx, SP_DP_AUX_CH_CTRL2_REG, &value); + if (err < 0) + return false; + + return (value & SP_AUX_EN) == 0; +} + +static int anx_aux_wait(struct regmap *map_dptx) +{ + unsigned long timeout; + unsigned int status; + int err; + + timeout = jiffies + msecs_to_jiffies(AUX_WAIT_TIMEOUT_MS) + 1; + + while (!anx_aux_op_finished(map_dptx)) { + if (time_after(jiffies, timeout)) { + if (!anx_aux_op_finished(map_dptx)) { + DRM_ERROR("Timed out waiting AUX to finish\n"); + return -ETIMEDOUT; + } + + break; + } + + usleep_range(1000, 2000); + } + + /* Read the AUX channel access status */ + err = regmap_read(map_dptx, SP_AUX_CH_STATUS_REG, &status); + if (err < 0) { + DRM_ERROR("Failed to read from AUX channel: %d\n", err); + return err; + } + + if (status & SP_AUX_STATUS) { + DRM_ERROR("Failed to wait for AUX channel (status: %02x)\n", + status); + return -ETIMEDOUT; + } + + return 0; +} + +static int anx_aux_address(struct regmap *map_dptx, unsigned int addr) +{ + int err; + + err = regmap_write(map_dptx, SP_AUX_ADDR_7_0_REG, addr & 0xff); + if (err) + return err; + + err = regmap_write(map_dptx, SP_AUX_ADDR_15_8_REG, + (addr & 0xff00) >> 8); + if (err) + return err; + + /* + * DP AUX CH Address Register #2, only update bits[3:0] + * [7:4] RESERVED + * [3:0] AUX_ADDR[19:16], Register control AUX CH address. + */ + err = regmap_update_bits(map_dptx, SP_AUX_ADDR_19_16_REG, + SP_AUX_ADDR_19_16_MASK, + (addr & 0xf0000) >> 16); + + if (err) + return err; + + return 0; +} + +ssize_t anx_aux_transfer(struct regmap *map_dptx, struct drm_dp_aux_msg *msg) +{ + u8 ctrl1 = msg->request; + u8 ctrl2 = SP_AUX_EN; + u8 *buffer = msg->buffer; + int err; + + /* The DP AUX transmit and receive buffer has 16 bytes. */ + if (WARN_ON(msg->size > AUX_CH_BUFFER_SIZE)) + return -E2BIG; + + /* Zero-sized messages specify address-only transactions. */ + if (msg->size < 1) + ctrl2 |= SP_ADDR_ONLY; + else /* For non-zero-sized set the length field. */ + ctrl1 |= (msg->size - 1) << SP_AUX_LENGTH_SHIFT; + + if ((msg->request & DP_AUX_I2C_READ) == 0) { + /* When WRITE | MOT write values to data buffer */ + err = regmap_bulk_write(map_dptx, + SP_DP_BUF_DATA0_REG, buffer, + msg->size); + if (err) + return err; + } + + /* Write address and request */ + err = anx_aux_address(map_dptx, msg->address); + if (err) + return err; + + err = regmap_write(map_dptx, SP_DP_AUX_CH_CTRL1_REG, ctrl1); + if (err) + return err; + + /* Start transaction */ + err = regmap_update_bits(map_dptx, SP_DP_AUX_CH_CTRL2_REG, + SP_ADDR_ONLY | SP_AUX_EN, ctrl2); + if (err) + return err; + + err = anx_aux_wait(map_dptx); + if (err) + return err; + + msg->reply = DP_AUX_I2C_REPLY_ACK; + + if ((msg->size > 0) && (msg->request & DP_AUX_I2C_READ)) { + /* Read values from data buffer */ + err = regmap_bulk_read(map_dptx, + SP_DP_BUF_DATA0_REG, buffer, + msg->size); + if (err) + return err; + } + + err = anx_clear_bits(map_dptx, SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY); + if (err) + return err; + + return msg->size; +} +EXPORT_SYMBOL(anx_aux_transfer); + +MODULE_DESCRIPTION("Analogix DisplayPort Transmitter common code"); +MODULE_AUTHOR("Icenowy Zheng <icenowy-h8G6r0blFSE@public.gmane.org>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h index bc0831b127bf..c2ca854613a0 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h +++ b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h @@ -245,4 +245,6 @@ /* DP AUX Buffer Data Registers */ #define SP_DP_BUF_DATA0_REG 0xf0 +ssize_t anx_aux_transfer(struct regmap *map_dptx, struct drm_dp_aux_msg *msg); + #endif -- 2.20.1
WARNING: multiple messages have this Message-ID (diff)
From: Vasily Khoruzhick <anarsoul@gmail.com> To: David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>, Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Thierry Reding <thierry.reding@gmail.com>, Maxime Ripard <maxime.ripard@bootlin.com>, Chen-Yu Tsai <wens@csie.org>, Archit Taneja <architt@codeaurora.org>, Andrzej Hajda <a.hajda@samsung.com>, Laurent Pinchart <Laurent.pinchart@ideasonboard.com>, Icenowy Zheng <icenowy@aosc.io>, Sean Paul <seanpaul@chromium.org>, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@googlegroups.com Subject: [PATCH RESEND v2 03/12] drm/bridge: extract some Analogix I2C DP common code Date: Sun, 3 Feb 2019 10:54:52 -0800 [thread overview] Message-ID: <20190203185501.8958-4-anarsoul@gmail.com> (raw) In-Reply-To: <20190203185501.8958-1-anarsoul@gmail.com> From: Icenowy Zheng <icenowy@aosc.io> Some code can be shared within different DP bridges by Analogix. Extract them to a new module. Signed-off-by: Icenowy Zheng <icenowy@aosc.io> Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com> --- drivers/gpu/drm/bridge/analogix/Kconfig | 4 + drivers/gpu/drm/bridge/analogix/Makefile | 2 + .../drm/bridge/analogix/analogix-anx78xx.c | 146 +-------------- .../drm/bridge/analogix/analogix-i2c-dptx.c | 169 ++++++++++++++++++ .../drm/bridge/analogix/analogix-i2c-dptx.h | 2 + 5 files changed, 178 insertions(+), 145 deletions(-) create mode 100644 drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c diff --git a/drivers/gpu/drm/bridge/analogix/Kconfig b/drivers/gpu/drm/bridge/analogix/Kconfig index c4d343a2f04d..ed2d05c12546 100644 --- a/drivers/gpu/drm/bridge/analogix/Kconfig +++ b/drivers/gpu/drm/bridge/analogix/Kconfig @@ -1,5 +1,6 @@ config DRM_ANALOGIX_ANX78XX tristate "Analogix ANX78XX bridge" + select DRM_ANALOGIX_DP_I2C select DRM_KMS_HELPER select REGMAP_I2C help @@ -11,3 +12,6 @@ config DRM_ANALOGIX_ANX78XX config DRM_ANALOGIX_DP tristate depends on DRM + +config DRM_ANALOGIX_DP_I2C + tristate diff --git a/drivers/gpu/drm/bridge/analogix/Makefile b/drivers/gpu/drm/bridge/analogix/Makefile index ce1687e60975..2d523b67487d 100644 --- a/drivers/gpu/drm/bridge/analogix/Makefile +++ b/drivers/gpu/drm/bridge/analogix/Makefile @@ -1,3 +1,5 @@ analogix_dp-objs := analogix_dp_core.o analogix_dp_reg.o +analogix_dp_i2c-objs := analogix-i2c-dptx.o obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix_dp.o +obj-$(CONFIG_DRM_ANALOGIX_DP_I2C) += analogix_dp_i2c.o diff --git a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c index f8433c93f463..bf8291d0ddd0 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c +++ b/drivers/gpu/drm/bridge/analogix/analogix-anx78xx.c @@ -45,8 +45,6 @@ #define I2C_IDX_RX_P1 4 #define XTAL_CLK 270 /* 27M */ -#define AUX_CH_BUFFER_SIZE 16 -#define AUX_WAIT_TIMEOUT_MS 15 static const u8 anx78xx_i2c_addresses[] = { [I2C_IDX_TX_P0] = TX_P0, @@ -109,153 +107,11 @@ static int anx78xx_clear_bits(struct regmap *map, u8 reg, u8 mask) return regmap_update_bits(map, reg, mask, 0); } -static bool anx78xx_aux_op_finished(struct anx78xx *anx78xx) -{ - unsigned int value; - int err; - - err = regmap_read(anx78xx->map[I2C_IDX_TX_P0], SP_DP_AUX_CH_CTRL2_REG, - &value); - if (err < 0) - return false; - - return (value & SP_AUX_EN) == 0; -} - -static int anx78xx_aux_wait(struct anx78xx *anx78xx) -{ - unsigned long timeout; - unsigned int status; - int err; - - timeout = jiffies + msecs_to_jiffies(AUX_WAIT_TIMEOUT_MS) + 1; - - while (!anx78xx_aux_op_finished(anx78xx)) { - if (time_after(jiffies, timeout)) { - if (!anx78xx_aux_op_finished(anx78xx)) { - DRM_ERROR("Timed out waiting AUX to finish\n"); - return -ETIMEDOUT; - } - - break; - } - - usleep_range(1000, 2000); - } - - /* Read the AUX channel access status */ - err = regmap_read(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_CH_STATUS_REG, - &status); - if (err < 0) { - DRM_ERROR("Failed to read from AUX channel: %d\n", err); - return err; - } - - if (status & SP_AUX_STATUS) { - DRM_ERROR("Failed to wait for AUX channel (status: %02x)\n", - status); - return -ETIMEDOUT; - } - - return 0; -} - -static int anx78xx_aux_address(struct anx78xx *anx78xx, unsigned int addr) -{ - int err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_ADDR_7_0_REG, - addr & 0xff); - if (err) - return err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_AUX_ADDR_15_8_REG, - (addr & 0xff00) >> 8); - if (err) - return err; - - /* - * DP AUX CH Address Register #2, only update bits[3:0] - * [7:4] RESERVED - * [3:0] AUX_ADDR[19:16], Register control AUX CH address. - */ - err = regmap_update_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_AUX_ADDR_19_16_REG, - SP_AUX_ADDR_19_16_MASK, - (addr & 0xf0000) >> 16); - - if (err) - return err; - - return 0; -} - static ssize_t anx78xx_aux_transfer(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg) { struct anx78xx *anx78xx = container_of(aux, struct anx78xx, aux); - u8 ctrl1 = msg->request; - u8 ctrl2 = SP_AUX_EN; - u8 *buffer = msg->buffer; - int err; - - /* The DP AUX transmit and receive buffer has 16 bytes. */ - if (WARN_ON(msg->size > AUX_CH_BUFFER_SIZE)) - return -E2BIG; - - /* Zero-sized messages specify address-only transactions. */ - if (msg->size < 1) - ctrl2 |= SP_ADDR_ONLY; - else /* For non-zero-sized set the length field. */ - ctrl1 |= (msg->size - 1) << SP_AUX_LENGTH_SHIFT; - - if ((msg->request & DP_AUX_I2C_READ) == 0) { - /* When WRITE | MOT write values to data buffer */ - err = regmap_bulk_write(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_BUF_DATA0_REG, buffer, - msg->size); - if (err) - return err; - } - - /* Write address and request */ - err = anx78xx_aux_address(anx78xx, msg->address); - if (err) - return err; - - err = regmap_write(anx78xx->map[I2C_IDX_TX_P0], SP_DP_AUX_CH_CTRL1_REG, - ctrl1); - if (err) - return err; - - /* Start transaction */ - err = regmap_update_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY | - SP_AUX_EN, ctrl2); - if (err) - return err; - - err = anx78xx_aux_wait(anx78xx); - if (err) - return err; - - msg->reply = DP_AUX_I2C_REPLY_ACK; - - if ((msg->size > 0) && (msg->request & DP_AUX_I2C_READ)) { - /* Read values from data buffer */ - err = regmap_bulk_read(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_BUF_DATA0_REG, buffer, - msg->size); - if (err) - return err; - } - - err = anx78xx_clear_bits(anx78xx->map[I2C_IDX_TX_P0], - SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY); - if (err) - return err; - - return msg->size; + return anx_aux_transfer(anx78xx->map[I2C_IDX_TX_P0], msg); } static int anx78xx_set_hpd(struct anx78xx *anx78xx) diff --git a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c new file mode 100644 index 000000000000..9cb30962032e --- /dev/null +++ b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright(c) 2017 Icenowy Zheng <icenowy@aosc.io> + * + * Based on analogix-anx78xx.c, which is: + * Copyright(c) 2016, Analogix Semiconductor. All rights reserved. + */ + +#include <linux/module.h> +#include <linux/regmap.h> + +#include <drm/drm.h> +#include <drm/drmP.h> +#include <drm/drm_dp_helper.h> + +#include "analogix-i2c-dptx.h" + +#define AUX_WAIT_TIMEOUT_MS 15 +#define AUX_CH_BUFFER_SIZE 16 + +static int anx_clear_bits(struct regmap *map, u8 reg, u8 mask) +{ + return regmap_update_bits(map, reg, mask, 0); +} + +static bool anx_aux_op_finished(struct regmap *map_dptx) +{ + unsigned int value; + int err; + + err = regmap_read(map_dptx, SP_DP_AUX_CH_CTRL2_REG, &value); + if (err < 0) + return false; + + return (value & SP_AUX_EN) == 0; +} + +static int anx_aux_wait(struct regmap *map_dptx) +{ + unsigned long timeout; + unsigned int status; + int err; + + timeout = jiffies + msecs_to_jiffies(AUX_WAIT_TIMEOUT_MS) + 1; + + while (!anx_aux_op_finished(map_dptx)) { + if (time_after(jiffies, timeout)) { + if (!anx_aux_op_finished(map_dptx)) { + DRM_ERROR("Timed out waiting AUX to finish\n"); + return -ETIMEDOUT; + } + + break; + } + + usleep_range(1000, 2000); + } + + /* Read the AUX channel access status */ + err = regmap_read(map_dptx, SP_AUX_CH_STATUS_REG, &status); + if (err < 0) { + DRM_ERROR("Failed to read from AUX channel: %d\n", err); + return err; + } + + if (status & SP_AUX_STATUS) { + DRM_ERROR("Failed to wait for AUX channel (status: %02x)\n", + status); + return -ETIMEDOUT; + } + + return 0; +} + +static int anx_aux_address(struct regmap *map_dptx, unsigned int addr) +{ + int err; + + err = regmap_write(map_dptx, SP_AUX_ADDR_7_0_REG, addr & 0xff); + if (err) + return err; + + err = regmap_write(map_dptx, SP_AUX_ADDR_15_8_REG, + (addr & 0xff00) >> 8); + if (err) + return err; + + /* + * DP AUX CH Address Register #2, only update bits[3:0] + * [7:4] RESERVED + * [3:0] AUX_ADDR[19:16], Register control AUX CH address. + */ + err = regmap_update_bits(map_dptx, SP_AUX_ADDR_19_16_REG, + SP_AUX_ADDR_19_16_MASK, + (addr & 0xf0000) >> 16); + + if (err) + return err; + + return 0; +} + +ssize_t anx_aux_transfer(struct regmap *map_dptx, struct drm_dp_aux_msg *msg) +{ + u8 ctrl1 = msg->request; + u8 ctrl2 = SP_AUX_EN; + u8 *buffer = msg->buffer; + int err; + + /* The DP AUX transmit and receive buffer has 16 bytes. */ + if (WARN_ON(msg->size > AUX_CH_BUFFER_SIZE)) + return -E2BIG; + + /* Zero-sized messages specify address-only transactions. */ + if (msg->size < 1) + ctrl2 |= SP_ADDR_ONLY; + else /* For non-zero-sized set the length field. */ + ctrl1 |= (msg->size - 1) << SP_AUX_LENGTH_SHIFT; + + if ((msg->request & DP_AUX_I2C_READ) == 0) { + /* When WRITE | MOT write values to data buffer */ + err = regmap_bulk_write(map_dptx, + SP_DP_BUF_DATA0_REG, buffer, + msg->size); + if (err) + return err; + } + + /* Write address and request */ + err = anx_aux_address(map_dptx, msg->address); + if (err) + return err; + + err = regmap_write(map_dptx, SP_DP_AUX_CH_CTRL1_REG, ctrl1); + if (err) + return err; + + /* Start transaction */ + err = regmap_update_bits(map_dptx, SP_DP_AUX_CH_CTRL2_REG, + SP_ADDR_ONLY | SP_AUX_EN, ctrl2); + if (err) + return err; + + err = anx_aux_wait(map_dptx); + if (err) + return err; + + msg->reply = DP_AUX_I2C_REPLY_ACK; + + if ((msg->size > 0) && (msg->request & DP_AUX_I2C_READ)) { + /* Read values from data buffer */ + err = regmap_bulk_read(map_dptx, + SP_DP_BUF_DATA0_REG, buffer, + msg->size); + if (err) + return err; + } + + err = anx_clear_bits(map_dptx, SP_DP_AUX_CH_CTRL2_REG, SP_ADDR_ONLY); + if (err) + return err; + + return msg->size; +} +EXPORT_SYMBOL(anx_aux_transfer); + +MODULE_DESCRIPTION("Analogix DisplayPort Transmitter common code"); +MODULE_AUTHOR("Icenowy Zheng <icenowy@aosc.io>"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h index bc0831b127bf..c2ca854613a0 100644 --- a/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h +++ b/drivers/gpu/drm/bridge/analogix/analogix-i2c-dptx.h @@ -245,4 +245,6 @@ /* DP AUX Buffer Data Registers */ #define SP_DP_BUF_DATA0_REG 0xf0 +ssize_t anx_aux_transfer(struct regmap *map_dptx, struct drm_dp_aux_msg *msg); + #endif -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-02-03 18:54 UTC|newest] Thread overview: 176+ messages / expand[flat|nested] mbox.gz Atom feed top 2019-02-03 18:54 [PATCH RESEND v2 00/12] Analogix ANX6345 RGB-(e)DP bridge support Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick [not found] ` <20190203185501.8958-1-anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2019-02-03 18:54 ` [PATCH RESEND v2 01/12] drm/bridge: move ANA78xx driver to analogix subdirectory Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:54 ` [PATCH RESEND v2 02/12] drm/bridge: split some definitions of ANX78xx to dedicated headers Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick [this message] 2019-02-03 18:54 ` [PATCH RESEND v2 03/12] drm/bridge: extract some Analogix I2C DP common code Vasily Khoruzhick 2019-02-03 18:54 ` [PATCH RESEND v2 04/12] dt-bindings: Add ANX6345 DP/eDP transmitter binding Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:54 ` [PATCH RESEND v2 05/12] drm/bridge: Add Analogix anx6345 support Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-05 13:19 ` Torsten Duwe 2019-02-05 13:19 ` Torsten Duwe 2019-02-03 18:54 ` [PATCH RESEND v2 06/12] drm/sun4i: rgb: Add 1% tolerance to dclk frequency check when bridge is connected Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick [not found] ` <20190203185501.8958-7-anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2019-02-04 14:20 ` Maxime Ripard 2019-02-04 14:20 ` Maxime Ripard 2019-02-04 16:26 ` Vasily Khoruzhick 2019-02-04 16:26 ` Vasily Khoruzhick [not found] ` <CA+E=qVfTfJ9E29gz83tdVGx5_KGWSQVJOAxKTzC+-n7=gdj0cA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 16:28 ` Icenowy Zheng 2019-02-04 16:28 ` Icenowy Zheng [not found] ` <0F6CBEA4-6DB6-40F1-A2FD-65101AF64F1F-h8G6r0blFSE@public.gmane.org> 2019-02-04 18:50 ` Vasily Khoruzhick 2019-02-04 18:50 ` [linux-sunxi] " Vasily Khoruzhick [not found] ` <CA+E=qVd7yh=JNZSvrfY4Diu+VJWFK6yLUJ5MavBcZ8Cftn6f-Q-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-05 15:41 ` Maxime Ripard 2019-02-05 15:41 ` [linux-sunxi] " Maxime Ripard 2019-02-05 17:49 ` Vasily Khoruzhick 2019-02-05 17:49 ` [linux-sunxi] " Vasily Khoruzhick 2019-02-06 9:16 ` Maxime Ripard 2019-02-06 9:16 ` Maxime Ripard 2019-02-06 11:42 ` Thierry Reding 2019-02-06 11:42 ` Thierry Reding 2019-02-03 18:54 ` [PATCH RESEND v2 07/12] drm/panel: simple: don't fail if we don't have panel desc Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:54 ` [PATCH RESEND v2 08/12] dt-bindings: add binding for generic eDP panel Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick [not found] ` <20190203185501.8958-9-anarsoul-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2019-02-04 7:43 ` Thierry Reding 2019-02-04 7:43 ` Thierry Reding 2019-02-04 8:13 ` Vasily Khoruzhick 2019-02-04 8:13 ` Vasily Khoruzhick [not found] ` <CA+E=qVecudACOEXt74Kf=UA_F-uuHgEqHzKpYAq1ocMx3Sx+eQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 8:23 ` Thierry Reding 2019-02-04 8:23 ` Thierry Reding 2019-02-04 9:40 ` Daniel Vetter 2019-02-04 9:40 ` Daniel Vetter [not found] ` <20190204094012.GP3271-dv86pmgwkMBes7Z6vYuT8azUEOm+Xw19@public.gmane.org> 2019-02-04 11:22 ` Thierry Reding 2019-02-04 11:22 ` Thierry Reding 2019-02-04 15:59 ` Daniel Vetter 2019-02-04 15:59 ` Daniel Vetter [not found] ` <20190204155909.GU3271-dv86pmgwkMBes7Z6vYuT8azUEOm+Xw19@public.gmane.org> 2019-02-04 16:22 ` Thierry Reding 2019-02-04 16:22 ` Thierry Reding 2019-02-05 8:57 ` Daniel Vetter 2019-02-05 8:57 ` Daniel Vetter 2019-02-05 10:24 ` Thierry Reding 2019-02-05 10:24 ` Thierry Reding 2019-02-05 16:36 ` Daniel Vetter 2019-02-05 16:36 ` Daniel Vetter [not found] ` <20190205163649.GG3271-dv86pmgwkMBes7Z6vYuT8azUEOm+Xw19@public.gmane.org> 2019-02-14 19:51 ` Vasily Khoruzhick 2019-02-14 19:51 ` Vasily Khoruzhick 2019-02-14 20:05 ` Vasily Khoruzhick 2019-02-14 20:05 ` Vasily Khoruzhick [not found] ` <CA+E=qVcUsz=5s1+RqDdQ4Hm3_Q3jDFuZwuYXUuVx3ubFWmcG7w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-14 20:38 ` Rob Herring 2019-02-14 20:38 ` Rob Herring [not found] ` <CAL_JsqKQ0EmyYGYvz__ZZGN7_6jLezevHWc+psn82Uy6hWZXMA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-14 20:54 ` Vasily Khoruzhick 2019-02-14 20:54 ` Vasily Khoruzhick 2019-02-04 16:11 ` Vasily Khoruzhick 2019-02-04 16:11 ` Vasily Khoruzhick [not found] ` <CA+E=qVew+8__yrAud1gFnLQ8HCwDdGhVjV=c173HGvZxH=7zZQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 16:27 ` Thierry Reding 2019-02-04 16:27 ` Thierry Reding 2019-02-04 16:39 ` Rob Herring 2019-02-04 16:39 ` Rob Herring [not found] ` <CAL_JsqLAODca_U94hCi9O3E6XiUjAYCoL7_0gkf_eMY0nnT8Ag-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 17:02 ` Vasily Khoruzhick 2019-02-04 17:02 ` [linux-sunxi] " Vasily Khoruzhick 2019-02-04 16:27 ` Rob Herring 2019-02-04 16:27 ` Rob Herring [not found] ` <CAL_JsqKt1kOXmRNvkYsQ6AL69+TPZURKpDbKkkEUb2+KZ5hKjQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 16:56 ` Thierry Reding 2019-02-04 16:56 ` Thierry Reding 2019-02-04 17:07 ` Vasily Khoruzhick 2019-02-04 17:07 ` Vasily Khoruzhick 2019-02-04 20:23 ` Rob Herring 2019-02-04 20:23 ` Rob Herring [not found] ` <CAL_JsqJx98DfHZSafiXA8QiO=bn1zy8g6keQ15L=cUmbVkTTOA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2019-02-04 20:26 ` Vasily Khoruzhick 2019-02-04 20:26 ` Vasily Khoruzhick 2019-02-04 20:34 ` Rob Herring 2019-02-04 20:34 ` Rob Herring 2019-02-03 18:54 ` [PATCH RESEND v2 09/12] drm/panel: simple: add " Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:54 ` [PATCH RESEND v2 10/12] arm64: allwinner: a64: add pinmux for RGB666 LCD Vasily Khoruzhick 2019-02-03 18:54 ` Vasily Khoruzhick 2019-02-03 18:55 ` [PATCH RESEND v2 11/12] arm64: allwinner: a64: enable LCD-related hardware for Pinebook Vasily Khoruzhick 2019-02-03 18:55 ` Vasily Khoruzhick 2019-02-03 18:55 ` [PATCH RESEND v2 12/12] arm64: allwinner: a64: enable LCD-related hardware for TERES-I Vasily Khoruzhick 2019-02-03 18:55 ` Vasily Khoruzhick -- strict thread matches above, loose matches on Subject: below -- 2018-10-18 7:33 [PATCH 0/9] Analogix ANX6345 RGB-(e)DP bridge support Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 1/9] drm/bridge: move ANA78xx driver to analogix subdirectory Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 8:47 ` Laurent Pinchart 2018-10-18 8:47 ` Laurent Pinchart 2018-10-18 8:47 ` Laurent Pinchart 2018-10-18 7:33 ` [PATCH 2/9] drm/bridge: split some definitions of ANX78xx to dedicated headers Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 3/9] drm/bridge: extract some Analogix I2C DP common code Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 4/9] dt-bindings: Add ANX6345 DP/eDP transmitter binding Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 8:53 ` Laurent Pinchart 2018-10-18 8:53 ` Laurent Pinchart 2018-10-18 8:53 ` Laurent Pinchart 2018-10-18 10:00 ` Icenowy Zheng 2018-10-18 10:00 ` Icenowy Zheng 2018-10-18 11:23 ` Laurent Pinchart 2018-10-18 11:23 ` Laurent Pinchart 2018-10-18 11:23 ` Laurent Pinchart 2018-10-18 12:40 ` Icenowy Zheng 2018-10-18 12:40 ` Icenowy Zheng 2018-10-25 18:30 ` Rob Herring 2018-10-25 18:30 ` Rob Herring 2018-10-25 18:30 ` Rob Herring 2018-10-26 0:08 ` Icenowy Zheng 2018-10-26 0:08 ` Icenowy Zheng 2018-10-26 0:08 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 5/9] drm/bridge: Add Analogix anx6345 support Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 6/9] arm64: allwinner: a64: add pinmux for RGB666 LCD Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 7/9] arm64: allwinner: a64: enable ANX6345 bridge on Pinebook Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 15:17 ` Vasily Khoruzhick 2018-10-18 15:17 ` Vasily Khoruzhick 2018-10-19 5:50 ` Icenowy Zheng 2018-10-19 5:50 ` Icenowy Zheng 2018-10-19 5:50 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 8/9] arm64: allwinner: a64: enable ANX6345 bridge on TERES-I Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` [PATCH 9/9] [DO NOT MERGE] drm/sun4i: rgb: Add 5% tolerance to dot clock frequency check Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 7:33 ` Icenowy Zheng 2018-10-18 8:55 ` Laurent Pinchart 2018-10-18 8:55 ` Laurent Pinchart 2018-10-18 8:55 ` Laurent Pinchart 2018-10-18 9:18 ` Daniel Vetter 2018-10-18 9:18 ` Daniel Vetter 2018-10-18 9:42 ` Maxime Ripard 2018-10-18 9:42 ` Maxime Ripard 2018-10-18 9:42 ` Maxime Ripard 2018-10-18 11:31 ` Laurent Pinchart 2018-10-18 11:31 ` Laurent Pinchart 2018-10-18 11:31 ` Laurent Pinchart 2018-10-18 12:18 ` Maxime Ripard 2018-10-18 12:18 ` Maxime Ripard 2018-10-18 12:18 ` Maxime Ripard 2018-10-18 12:50 ` Icenowy Zheng 2018-10-18 12:50 ` Icenowy Zheng 2018-10-18 12:50 ` Icenowy Zheng 2018-10-18 13:07 ` Maxime Ripard 2018-10-18 13:07 ` Maxime Ripard 2018-10-18 13:07 ` Maxime Ripard 2018-10-18 13:57 ` Laurent Pinchart 2018-10-18 13:57 ` Laurent Pinchart 2018-10-18 13:57 ` Laurent Pinchart 2019-02-03 1:32 ` Vasily Khoruzhick 2019-02-03 1:32 ` Vasily Khoruzhick 2019-02-03 1:32 ` Vasily Khoruzhick 2018-10-18 12:25 ` Stefan Monnier 2018-10-29 2:20 ` [PATCH 0/9] Analogix ANX6345 RGB-(e)DP bridge support Vasily Khoruzhick 2018-10-29 2:20 ` Vasily Khoruzhick 2019-02-04 12:22 ` Torsten Duwe 2019-02-04 12:22 ` Torsten Duwe 2019-02-04 20:21 ` Vasily Khoruzhick 2019-02-04 20:21 ` Vasily Khoruzhick 2019-02-04 20:21 ` Vasily Khoruzhick
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