[PATCH v4 02/15] phy: Distinguish between Rx and Tx for MIPI D-PHY with submodes

From: Paul Kocialkowski
Date: Thu Dec 31 2020 - 09:30:53 EST


As some D-PHY controllers support both Rx and Tx mode, we need a way for
users to explicitly request one or the other. For instance, Rx mode can
be used along with MIPI CSI-2 while Tx mode can be used with MIPI DSI.

Introduce new MIPI D-PHY PHY submodes to use with PHY_MODE_MIPI_DPHY.
The default (zero value) is kept to Tx so only the rkisp1 driver, which
uses D-PHY in Rx mode, needs to be adapted.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@xxxxxxxxxxx>
Acked-by: Helen Koike <helen.koike@xxxxxxxxxxxxx>
---
drivers/staging/media/rkisp1/rkisp1-isp.c | 3 ++-
include/linux/phy/phy-mipi-dphy.h | 13 +++++++++++++
2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/rkisp1/rkisp1-isp.c b/drivers/staging/media/rkisp1/rkisp1-isp.c
index a9715b0b7264..f1167995688a 100644
--- a/drivers/staging/media/rkisp1/rkisp1-isp.c
+++ b/drivers/staging/media/rkisp1/rkisp1-isp.c
@@ -914,7 +914,8 @@ static int rkisp1_mipi_csi2_start(struct rkisp1_isp *isp,

phy_mipi_dphy_get_default_config(pixel_clock, isp->sink_fmt->bus_width,
sensor->lanes, cfg);
- phy_set_mode(sensor->dphy, PHY_MODE_MIPI_DPHY);
+ phy_set_mode_ext(cdev->dphy, PHY_MODE_MIPI_DPHY,
+ PHY_MIPI_DPHY_SUBMODE_RX);
phy_configure(sensor->dphy, &opts);
phy_power_on(sensor->dphy);

diff --git a/include/linux/phy/phy-mipi-dphy.h b/include/linux/phy/phy-mipi-dphy.h
index a877ffee845d..0f57ef46a8b5 100644
--- a/include/linux/phy/phy-mipi-dphy.h
+++ b/include/linux/phy/phy-mipi-dphy.h
@@ -6,6 +6,19 @@
#ifndef __PHY_MIPI_DPHY_H_
#define __PHY_MIPI_DPHY_H_

+/**
+ * enum phy_mipi_dphy_submode - MIPI D-PHY sub-mode
+ *
+ * A MIPI D-PHY can be used to transmit or receive data.
+ * Since some controllers can support both, the direction to enable is specified
+ * with the PHY sub-mode. Transmit is assumed by default with phy_set_mode.
+ */
+
+enum phy_mipi_dphy_submode {
+ PHY_MIPI_DPHY_SUBMODE_TX = 0,
+ PHY_MIPI_DPHY_SUBMODE_RX,
+};
+
/**
* struct phy_configure_opts_mipi_dphy - MIPI D-PHY configuration set
*
--
2.29.2