Re: [PATCH v11 09/12] drm/mediatek: add dsi transfer function

[CK Hu]

Hi, YT:

On Wed, 2017-01-11 at 14:51 +0800, YT Shen wrote:
> From: shaoming chen <shaoming.chen@xxxxxxxxxxxx>
> 
> add dsi read/write commands for transfer function
> 
> Signed-off-by: shaoming chen <shaoming.chen@xxxxxxxxxxxx>

Acked-by: CK Hu <ck.hu@xxxxxxxxxxxx>

> ---
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 168 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 166 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 474861a..b3c7fd8 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -24,6 +24,7 @@
>  #include <linux/of_graph.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <video/mipi_display.h>
>  #include <video/videomode.h>
>  
>  #include "mtk_drm_ddp_comp.h"
> @@ -80,8 +81,16 @@
>  #define DSI_HBP_WC		0x54
>  #define DSI_HFP_WC		0x58
>  
> +#define DSI_CMDQ_SIZE		0x60
> +#define CMDQ_SIZE			0x3f
> +
>  #define DSI_HSTX_CKL_WC		0x64
>  
> +#define DSI_RX_DATA0		0x74
> +#define DSI_RX_DATA1		0x78
> +#define DSI_RX_DATA2		0x7c
> +#define DSI_RX_DATA3		0x80
> +
>  #define DSI_RACK		0x84
>  #define RACK				BIT(0)
>  
> @@ -117,6 +126,15 @@
>  #define CLK_HS_POST			(0xff << 8)
>  #define CLK_HS_EXIT			(0xff << 16)
>  
> +#define DSI_CMDQ0		0x180
> +#define CONFIG				(0xff << 0)
> +#define SHORT_PACKET			0
> +#define LONG_PACKET			2
> +#define BTA				BIT(2)
> +#define DATA_ID				(0xff << 8)
> +#define DATA_0				(0xff << 16)
> +#define DATA_1				(0xff << 24)
> +
>  #define T_LPX		5
>  #define T_HS_PREP	6
>  #define T_HS_TRAIL	8
> @@ -125,6 +143,12 @@
>  
>  #define NS_TO_CYCLE(n, c)    ((n) / (c) + (((n) % (c)) ? 1 : 0))
>  
> +#define MTK_DSI_HOST_IS_READ(type) \
> +	((type == MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM) || \
> +	(type == MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM) || \
> +	(type == MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM) || \
> +	(type == MIPI_DSI_DCS_READ))
> +
>  struct phy;
>  
>  struct mtk_dsi {
> @@ -497,12 +521,12 @@ static void mtk_dsi_irq_data_set(struct mtk_dsi *dsi, u32 irq_bit)
>  	dsi->irq_data |= irq_bit;
>  }
>  
> -static __maybe_unused void mtk_dsi_irq_data_clear(struct mtk_dsi *dsi, u32 irq_bit)
> +static void mtk_dsi_irq_data_clear(struct mtk_dsi *dsi, u32 irq_bit)
>  {
>  	dsi->irq_data &= ~irq_bit;
>  }
>  
> -static __maybe_unused s32 mtk_dsi_wait_for_irq_done(struct mtk_dsi *dsi, u32 irq_flag,
> +static s32 mtk_dsi_wait_for_irq_done(struct mtk_dsi *dsi, u32 irq_flag,
>  				     unsigned int timeout)
>  {
>  	s32 ret = 0;
> @@ -832,9 +856,149 @@ static int mtk_dsi_host_detach(struct mipi_dsi_host *host,
>  	return 0;
>  }
>  
> +static void mtk_dsi_wait_for_idle(struct mtk_dsi *dsi)
> +{
> +	u32 timeout_ms = 500000; /* total 1s ~ 2s timeout */
> +
> +	while (timeout_ms--) {
> +		if (!(readl(dsi->regs + DSI_INTSTA) & DSI_BUSY))
> +			break;
> +
> +		usleep_range(2, 4);
> +	}
> +
> +	if (timeout_ms == 0) {
> +		DRM_WARN("polling dsi wait not busy timeout!\n");
> +
> +		mtk_dsi_enable(dsi);
> +		mtk_dsi_reset_engine(dsi);
> +	}
> +}
> +
> +static u32 mtk_dsi_recv_cnt(u8 type, u8 *read_data)
> +{
> +	switch (type) {
> +	case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
> +	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
> +		return 1;
> +	case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
> +	case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
> +		return 2;
> +	case MIPI_DSI_RX_GENERIC_LONG_READ_RESPONSE:
> +	case MIPI_DSI_RX_DCS_LONG_READ_RESPONSE:
> +		return read_data[1] + read_data[2] * 16;
> +	case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
> +		DRM_INFO("type is 0x02, try again\n");
> +		break;
> +	default:
> +		DRM_INFO("type(0x%x) cannot be non-recognite\n", type);
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
> +static void mtk_dsi_cmdq(struct mtk_dsi *dsi, const struct mipi_dsi_msg *msg)
> +{
> +	const char *tx_buf = msg->tx_buf;
> +	u8 config, cmdq_size, cmdq_off, type = msg->type;
> +	u32 reg_val, cmdq_mask, i;
> +
> +	if (MTK_DSI_HOST_IS_READ(type))
> +		config = BTA;
> +	else
> +		config = (msg->tx_len > 2) ? LONG_PACKET : SHORT_PACKET;
> +
> +	if (msg->tx_len > 2) {
> +		cmdq_size = 1 + (msg->tx_len + 3) / 4;
> +		cmdq_off = 4;
> +		cmdq_mask = CONFIG | DATA_ID | DATA_0 | DATA_1;
> +		reg_val = (msg->tx_len << 16) | (type << 8) | config;
> +	} else {
> +		cmdq_size = 1;
> +		cmdq_off = 2;
> +		cmdq_mask = CONFIG | DATA_ID;
> +		reg_val = (type << 8) | config;
> +	}
> +
> +	for (i = 0; i < msg->tx_len; i++)
> +		writeb(tx_buf[i], dsi->regs + DSI_CMDQ0 + cmdq_off + i);
> +
> +	mtk_dsi_mask(dsi, DSI_CMDQ0, cmdq_mask, reg_val);
> +	mtk_dsi_mask(dsi, DSI_CMDQ_SIZE, CMDQ_SIZE, cmdq_size);
> +}
> +
> +static ssize_t mtk_dsi_host_send_cmd(struct mtk_dsi *dsi,
> +				     const struct mipi_dsi_msg *msg, u8 flag)
> +{
> +	mtk_dsi_wait_for_idle(dsi);
> +	mtk_dsi_irq_data_clear(dsi, flag);
> +	mtk_dsi_cmdq(dsi, msg);
> +	mtk_dsi_start(dsi);
> +
> +	if (!mtk_dsi_wait_for_irq_done(dsi, flag, 2000))
> +		return -ETIME;
> +	else
> +		return 0;
> +}
> +
> +static ssize_t mtk_dsi_host_transfer(struct mipi_dsi_host *host,
> +				     const struct mipi_dsi_msg *msg)
> +{
> +	struct mtk_dsi *dsi = host_to_dsi(host);
> +	u32 recv_cnt, i;
> +	u8 read_data[16];
> +	void *src_addr;
> +	u8 irq_flag = CMD_DONE_INT_FLAG;
> +
> +	if (readl(dsi->regs + DSI_MODE_CTRL) & MODE) {
> +		DRM_ERROR("dsi engine is not command mode\n");
> +		return -EINVAL;
> +	}
> +
> +	if (MTK_DSI_HOST_IS_READ(msg->type))
> +		irq_flag |= LPRX_RD_RDY_INT_FLAG;
> +
> +	if (mtk_dsi_host_send_cmd(dsi, msg, irq_flag) < 0)
> +		return -ETIME;
> +
> +	if (!MTK_DSI_HOST_IS_READ(msg->type))
> +		return 0;
> +
> +	if (!msg->rx_buf) {
> +		DRM_ERROR("dsi receive buffer size may be NULL\n");
> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < 16; i++)
> +		*(read_data + i) = readb(dsi->regs + DSI_RX_DATA0 + i);
> +
> +	recv_cnt = mtk_dsi_recv_cnt(read_data[0], read_data);
> +
> +	if (recv_cnt > 2)
> +		src_addr = &read_data[4];
> +	else
> +		src_addr = &read_data[1];
> +
> +	if (recv_cnt > 10)
> +		recv_cnt = 10;
> +
> +	if (recv_cnt > msg->rx_len)
> +		recv_cnt = msg->rx_len;
> +
> +	if (recv_cnt)
> +		memcpy(msg->rx_buf, src_addr, recv_cnt);
> +
> +	DRM_INFO("dsi get %d byte data from the panel address(0x%x)\n",
> +		 recv_cnt, *((u8 *)(msg->tx_buf)));
> +
> +	return recv_cnt;
> +}
> +
>  static const struct mipi_dsi_host_ops mtk_dsi_ops = {
>  	.attach = mtk_dsi_host_attach,
>  	.detach = mtk_dsi_host_detach,
> +	.transfer = mtk_dsi_host_transfer,
>  };
>  
>  static int mtk_dsi_bind(struct device *dev, struct device *master, void *data)