Re: [PATCH v5 1/2] drm/bridge: Add Cadence DSI driver

On Mon, 29 Jan 2018 13:56:21 +0200 Tomi Valkeinen tomi.valkeinen@ti.com wrote:

...

+static ssize_t cdns_dsi_transfer(struct mipi_dsi_host *host,

• 		 const struct mipi_dsi_msg *msg)
  

+{

• struct cdns_dsi *dsi = to_cdns_dsi(host);
• u32 cmd, sts, val, wait = WRITE_COMPLETED, ctl = 0;
• struct mipi_dsi_packet packet;
• int ret, i, tx_len, rx_len;
• ret = pm_runtime_get_sync(host->dev);
• if (ret < 0)

• return ret;
  

• cdns_dsi_init_link(dsi);
• ret = mipi_dsi_create_packet(&packet, msg);
• if (ret)

• goto out;
  

• tx_len = msg->tx_buf ? msg->tx_len : 0;
• rx_len = msg->rx_buf ? msg->rx_len : 0;
• /* For read operations, the maximum TX len is 2. */
• if (rx_len && tx_len > 2) {

• ret = -ENOTSUPP;
  

• goto out;
  

• }
• /* TX len is limited by the CMD FIFO depth. */
• if (tx_len > dsi->direct_cmd_fifo_depth) {

• ret = -ENOTSUPP;
  

• goto out;
  

• }
• /* RX len is limited by the RX FIFO depth. */
• if (rx_len > dsi->rx_fifo_depth) {

• ret = -ENOTSUPP;
  

• goto out;
  

• }
• cmd = CMD_SIZE(tx_len) | CMD_VCHAN_ID(msg->channel) |

•      CMD_DATATYPE(msg->type);
  

• if (msg->flags & MIPI_DSI_MSG_USE_LPM)

• cmd |= CMD_LP_EN;
  

• if (mipi_dsi_packet_format_is_long(msg->type))

• cmd |= CMD_LONG;
  

• if (rx_len) {

• cmd |= READ_CMD;
  

• wait = READ_COMPLETED_WITH_ERR | READ_COMPLETED;
  

• ctl = READ_EN | BTA_EN;
  

• } else if (msg->flags & MIPI_DSI_MSG_REQ_ACK) {

• cmd |= BTA_REQ;
  

• wait = ACK_WITH_ERR_RCVD | ACK_RCVD;
  

• ctl = BTA_EN;
  

• }
• writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) | ctl,

•       dsi->regs + MCTL_MAIN_DATA_CTL);
  

• writel(cmd, dsi->regs + DIRECT_CMD_MAIN_SETTINGS);
• for (i = 0; i < tx_len; i += 4) {

• const u8 *buf = msg->tx_buf;
  

• int j;
  

• val = 0;
  

• for (j = 0; j < 4 && j + i < tx_len; j++)
  

• 	val |= (u32)buf[i + j] << (8 * j);
  

• writel(val, dsi->regs + DIRECT_CMD_WRDATA);
  

• }
• /* Clear status flags before sending the command. */
• writel(wait, dsi->regs + DIRECT_CMD_STS_CLR);
• writel(wait, dsi->regs + DIRECT_CMD_STS_CTL);
• reinit_completion(&dsi->direct_cmd_comp);
• writel(0, dsi->regs + DIRECT_CMD_SEND);
• wait_for_completion_timeout(&dsi->direct_cmd_comp,

• 		    msecs_to_jiffies(1000));
  

• sts = readl(dsi->regs + DIRECT_CMD_STS);
• writel(wait, dsi->regs + DIRECT_CMD_STS_CLR);
• writel(0, dsi->regs + DIRECT_CMD_STS_CTL);
• writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) & ~ctl,

•       dsi->regs + MCTL_MAIN_DATA_CTL);
  

• /* We did not receive the events we were waiting for. */
• if (!(sts & wait)) {

• ret = -ETIMEDOUT;
  

• goto out;
  

• }
• /* READ of WRITE with ACK failed. */

Should that 'of' be 'or'?

Yep, I'll fix that too.

Other than those trivial changes, are you happy with the rest of the driver or should I wait a bit for a full review?