Hi,
This series adds support for Cadence DPHY Rx driver. It has been split
off from [0] to facilitate easier merging. I have still kept the version
number to maintain continuity with the previous patches. The earlier
version used the same binding for Tx and Rx DPHY. With the separate
driver, I have added a separate binding. But I am still keeping the old
conversion patch in this series since I have already done the work in
converting the binding to yaml, might as well get it merged.
Tested on TI's J721E with OV5640 sensor.
[0] https://patchwork.linuxtv.org/project/linux-media/list/?series=5526&state=%2A&archive=both
Changes in v6:
- Add a new binding for DPHY Rx.
- Move the DPHY Rx part to a separate driver.
- Drop Rx specific changes from the cdns,dphy.yaml binding. Keep those
in cdns,dphy-rx.yaml
Changes in v5:
- Use the new cdns_dphy_info to specify PHY ops.
- Re-order include in alphabetical order.
- Make bands const.
- Drop num_bands.
- Make i, lanes unsigned.
- Drop the maximum check in cdns_dphy_rx_get_band_ctrl(). Let the loop
complete and return -EOPNOTSUPP when we reach the end.
- Drop the "rate < bands[i].min_rate" check since the bands are in
ascending order.
- Move data_lane_ctrl to start of function and make it static const.
Changes in v4:
- Drop the submode parts. Use a different compatible for the Rx ops.
- Make bands and num_bands static.
- Drop the submode patches. Use a different compatible for Rx mode DPHY
instead.
Changes in v3:
- Use a table to select the band.
- Use a table to poll the data lane ready bits.
- Multiply the DPHY HS clock rate by 2 to get the bit rate since the
clock is DDR.
- Add Rob's R-by.
Changes in v2:
- Drop reg description.
- Add a description for each DPHY clock.
- Rename dphy@... to phy@... in example.
- Add Laurent's R-by.
- Re-order subject prefixes.
- Add power-domain to the example.
- Add Laurent's R-by.
- Re-order subject prefixes.
Pratyush Yadav (4):
phy: cadence: Add Cadence D-PHY Rx driver
phy: dt-bindings: Convert Cadence DPHY binding to YAML
phy: dt-bindings: cdns,dphy: add power-domains property
phy: dt-bindings: Add Cadence D-PHY Rx bindings
.../devicetree/bindings/phy/cdns,dphy-rx.yaml | 42 +++
.../devicetree/bindings/phy/cdns,dphy.txt | 20 --
.../devicetree/bindings/phy/cdns,dphy.yaml | 56 ++++
drivers/phy/cadence/Kconfig | 8 +
drivers/phy/cadence/Makefile | 1 +
drivers/phy/cadence/cdns-dphy-rx.c | 250 ++++++++++++++++++
6 files changed, 357 insertions(+), 20 deletions(-)
create mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml
delete mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy.txt
create mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy.yaml
create mode 100644 drivers/phy/cadence/cdns-dphy-rx.c
--
2.33.1.835.ge9e5ba39a7
The Cadence D-PHY can be configured in Tx (DSI) mode or Rx (CSI) mode.
Both modes have a different programming sequence and share little among
them. In addition, a PHY configured in Tx mode cannot be used in Rx mode
and vice versa. For this reason, create a separate driver for the Rx
mode to make it easier to read and maintain.
Signed-off-by: Pratyush Yadav <[email protected]>
---
Changes in v6:
- Move to a separate driver.
Changes in v5:
- Use the new cdns_dphy_info to specify PHY ops.
- Re-order include in alphabetical order.
- Make bands const.
- Drop num_bands.
- Make i, lanes unsigned.
- Drop the maximum check in cdns_dphy_rx_get_band_ctrl(). Let the loop
complete and return -EOPNOTSUPP when we reach the end.
- Drop the "rate < bands[i].min_rate" check since the bands are in
ascending order.
- Move data_lane_ctrl to start of function and make it static const.
Changes in v4:
- Drop the submode parts. Use a different compatible for the Rx ops.
- Make bands and num_bands static.
Changes in v3:
- Use a table to select the band.
- Use a table to poll the data lane ready bits.
- Multiply the DPHY HS clock rate by 2 to get the bit rate since the
clock is DDR.
drivers/phy/cadence/Kconfig | 8 +
drivers/phy/cadence/Makefile | 1 +
drivers/phy/cadence/cdns-dphy-rx.c | 250 +++++++++++++++++++++++++++++
3 files changed, 259 insertions(+)
create mode 100644 drivers/phy/cadence/cdns-dphy-rx.c
diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
index a62910ff5591..1adde2d99ae7 100644
--- a/drivers/phy/cadence/Kconfig
+++ b/drivers/phy/cadence/Kconfig
@@ -22,6 +22,14 @@ config PHY_CADENCE_DPHY
system. If M is selected, the module will be called
cdns-dphy.
+config PHY_CADENCE_DPHY_RX
+ tristate "Cadence D-PHY Rx Support"
+ depends on HAS_IOMEM && OF
+ select GENERIC_PHY
+ select GENERIC_PHY_MIPI_DPHY
+ help
+ Support for Cadence D-PHY in Rx configuration.
+
config PHY_CADENCE_SIERRA
tristate "Cadence Sierra PHY Driver"
depends on OF && HAS_IOMEM && RESET_CONTROLLER
diff --git a/drivers/phy/cadence/Makefile b/drivers/phy/cadence/Makefile
index 26e16bd34efe..e17f035ddece 100644
--- a/drivers/phy/cadence/Makefile
+++ b/drivers/phy/cadence/Makefile
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_PHY_CADENCE_TORRENT) += phy-cadence-torrent.o
obj-$(CONFIG_PHY_CADENCE_DPHY) += cdns-dphy.o
+obj-$(CONFIG_PHY_CADENCE_DPHY_RX) += cdns-dphy-rx.o
obj-$(CONFIG_PHY_CADENCE_SIERRA) += phy-cadence-sierra.o
obj-$(CONFIG_PHY_CADENCE_SALVO) += phy-cadence-salvo.o
diff --git a/drivers/phy/cadence/cdns-dphy-rx.c b/drivers/phy/cadence/cdns-dphy-rx.c
new file mode 100644
index 000000000000..fb75e645e662
--- /dev/null
+++ b/drivers/phy/cadence/cdns-dphy-rx.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/phy/phy.h>
+#include <linux/phy/phy-mipi-dphy.h>
+#include <linux/platform_device.h>
+
+#define DPHY_PMA_CMN(reg) (reg)
+#define DPHY_PCS(reg) (0xb00 + (reg))
+#define DPHY_ISO(reg) (0xc00 + (reg))
+
+#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
+#define DPHY_CMN_RX_MODE_EN BIT(10)
+#define DPHY_CMN_RX_BANDGAP_TIMER_MASK GENMASK(8, 1)
+#define DPHY_CMN_SSM_EN BIT(0)
+
+#define DPHY_CMN_RX_BANDGAP_TIMER 0x14
+
+#define DPHY_BAND_CFG DPHY_PCS(0x0)
+#define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
+#define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
+
+#define DPHY_POWER_ISLAND_EN_DATA DPHY_PCS(0x8)
+#define DPHY_POWER_ISLAND_EN_DATA_VAL 0xaaaaaaaa
+
+#define DPHY_POWER_ISLAND_EN_CLK DPHY_PCS(0xc)
+#define DPHY_POWER_ISLAND_EN_CLK_VAL 0xaa
+
+#define DPHY_ISO_CL_CTRL_L DPHY_ISO(0x10)
+#define DPHY_ISO_DL_CTRL_L0 DPHY_ISO(0x14)
+#define DPHY_ISO_DL_CTRL_L1 DPHY_ISO(0x20)
+#define DPHY_ISO_DL_CTRL_L2 DPHY_ISO(0x30)
+#define DPHY_ISO_DL_CTRL_L3 DPHY_ISO(0x3c)
+
+#define DPHY_ISO_LANE_READY_BIT 0
+#define DPHY_ISO_LANE_READY_TIMEOUT_MS 100UL
+
+#define DPHY_LANES_MIN 1
+#define DPHY_LANES_MAX 4
+
+struct cdns_dphy_rx {
+ void __iomem *regs;
+ struct device *dev;
+ struct phy *phy;
+};
+
+struct cdns_dphy_rx_band {
+ /* Rates are in Mbps. */
+ unsigned int min_rate;
+ unsigned int max_rate;
+};
+
+/* Order of bands is important since the index is the band number. */
+static const struct cdns_dphy_rx_band bands[] = {
+ {80, 100}, {100, 120}, {120, 160}, {160, 200}, {200, 240},
+ {240, 280}, {280, 320}, {320, 360}, {360, 400}, {400, 480},
+ {480, 560}, {560, 640}, {640, 720}, {720, 800}, {800, 880},
+ {880, 1040}, {1040, 1200}, {1200, 1350}, {1350, 1500}, {1500, 1750},
+ {1750, 2000}, {2000, 2250}, {2250, 2500}
+};
+
+static int cdns_dphy_rx_power_on(struct phy *phy)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+
+ /* Start RX state machine. */
+ writel(DPHY_CMN_SSM_EN | DPHY_CMN_RX_MODE_EN |
+ FIELD_PREP(DPHY_CMN_RX_BANDGAP_TIMER_MASK,
+ DPHY_CMN_RX_BANDGAP_TIMER),
+ dphy->regs + DPHY_CMN_SSM);
+
+ return 0;
+}
+
+static int cdns_dphy_rx_power_off(struct phy *phy)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+
+ writel(0, dphy->regs + DPHY_CMN_SSM);
+
+ return 0;
+}
+
+static int cdns_dphy_rx_get_band_ctrl(unsigned long hs_clk_rate)
+{
+ unsigned int rate, i;
+
+ rate = hs_clk_rate / 1000000UL;
+ /* Since CSI-2 clock is DDR, the bit rate is twice the clock rate. */
+ rate *= 2;
+
+ if (rate < bands[0].min_rate)
+ return -EOPNOTSUPP;
+
+ for (i = 0; i < ARRAY_SIZE(bands); i++) {
+ if (rate < bands[i].max_rate)
+ return i;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static int cdns_dphy_rx_wait_for_bit(void __iomem *addr, unsigned int bit)
+{
+ u32 val;
+
+ return readl_relaxed_poll_timeout(addr, val, val & BIT(bit), 10,
+ DPHY_ISO_LANE_READY_TIMEOUT_MS * 1000);
+}
+
+static int cdns_dphy_rx_wait_lane_ready(struct cdns_dphy_rx *dphy,
+ unsigned int lanes)
+{
+ static const u32 data_lane_ctrl[] = {DPHY_ISO_DL_CTRL_L0,
+ DPHY_ISO_DL_CTRL_L1,
+ DPHY_ISO_DL_CTRL_L2,
+ DPHY_ISO_DL_CTRL_L3};
+ void __iomem *reg = dphy->regs;
+ unsigned int i;
+ int ret;
+
+ /* Data lanes. Minimum one lane is mandatory. */
+ if (lanes < DPHY_LANES_MIN || lanes > DPHY_LANES_MAX)
+ return -EINVAL;
+
+ /* Clock lane */
+ ret = cdns_dphy_rx_wait_for_bit(reg + DPHY_ISO_CL_CTRL_L,
+ DPHY_ISO_LANE_READY_BIT);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < lanes; i++) {
+ ret = cdns_dphy_rx_wait_for_bit(reg + data_lane_ctrl[i],
+ DPHY_ISO_LANE_READY_BIT);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cdns_dphy_rx_configure(struct phy *phy,
+ union phy_configure_opts *opts)
+{
+ struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
+ unsigned int reg;
+ int band_ctrl, ret;
+
+ band_ctrl = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
+ if (band_ctrl < 0)
+ return band_ctrl;
+
+ reg = FIELD_PREP(DPHY_BAND_CFG_LEFT_BAND, band_ctrl) |
+ FIELD_PREP(DPHY_BAND_CFG_RIGHT_BAND, band_ctrl);
+ writel(reg, dphy->regs + DPHY_BAND_CFG);
+
+ /*
+ * Set the required power island phase 2 time. This is mandated by DPHY
+ * specs.
+ */
+ reg = DPHY_POWER_ISLAND_EN_DATA_VAL;
+ writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_DATA);
+ reg = DPHY_POWER_ISLAND_EN_CLK_VAL;
+ writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_CLK);
+
+ ret = cdns_dphy_rx_wait_lane_ready(dphy, opts->mipi_dphy.lanes);
+ if (ret) {
+ dev_err(dphy->dev, "DPHY wait for lane ready timeout\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int cdns_dphy_rx_validate(struct phy *phy, enum phy_mode mode,
+ int submode, union phy_configure_opts *opts)
+{
+ int ret;
+
+ if (mode != PHY_MODE_MIPI_DPHY)
+ return -EINVAL;
+
+ ret = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
+ if (ret < 0)
+ return ret;
+
+ return phy_mipi_dphy_config_validate(&opts->mipi_dphy);
+}
+
+static const struct phy_ops cdns_dphy_rx_ops = {
+ .power_on = cdns_dphy_rx_power_on,
+ .power_off = cdns_dphy_rx_power_off,
+ .configure = cdns_dphy_rx_configure,
+ .validate = cdns_dphy_rx_validate,
+};
+
+static int cdns_dphy_rx_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct phy_provider *provider;
+ struct cdns_dphy_rx *dphy;
+
+ dphy = devm_kzalloc(dev, sizeof(*dphy), GFP_KERNEL);
+ if (!dphy)
+ return -ENOMEM;
+
+ dev_set_drvdata(dev, dphy);
+ dphy->dev = dev;
+
+ dphy->regs = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(dphy->regs))
+ return PTR_ERR(dphy->regs);
+
+ dphy->phy = devm_phy_create(dev, NULL, &cdns_dphy_rx_ops);
+ if (IS_ERR(dphy->phy)) {
+ dev_err(dev, "Failed to create PHY: %d\n", PTR_ERR(dphy->phy));
+ return PTR_ERR(dphy->phy);
+ }
+
+ phy_set_drvdata(dphy->phy, dphy);
+ provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+ return PTR_ERR_OR_ZERO(provider);
+}
+
+static const struct of_device_id cdns_dphy_rx_of_match[] = {
+ { .compatible = "cdns,dphy-rx" },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, cdns_dphy_rx_of_match);
+
+static struct platform_driver cdns_dphy_rx_platform_driver = {
+ .probe = cdns_dphy_rx_probe,
+ .driver = {
+ .name = "cdns-mipi-dphy-rx",
+ .of_match_table = cdns_dphy_rx_of_match,
+ },
+};
+module_platform_driver(cdns_dphy_rx_platform_driver);
+
+MODULE_AUTHOR("Pratyush Yadav <[email protected]>");
+MODULE_DESCRIPTION("Cadence D-PHY Rx Driver");
+MODULE_LICENSE("GPL v2");
--
2.33.1.835.ge9e5ba39a7
The Rx mode DPHY is different from Tx mode DPHY. Add a separate binding
for it.
Signed-off-by: Pratyush Yadav <[email protected]>
---
Changes in v6:
- Add a new binding for DPHY Rx.
.../devicetree/bindings/phy/cdns,dphy-rx.yaml | 42 +++++++++++++++++++
1 file changed, 42 insertions(+)
create mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml
diff --git a/Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml b/Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml
new file mode 100644
index 000000000000..07be031d82e6
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml
@@ -0,0 +1,42 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/cdns,dphy-rx.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cadence DPHY Rx Device Tree Bindings
+
+maintainers:
+ - Pratyush Yadav <[email protected]>
+
+properties:
+ compatible:
+ items:
+ - const: cdns,dphy-rx
+
+ reg:
+ maxItems: 1
+
+ "#phy-cells":
+ const: 0
+
+ power-domains:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/soc/ti,sci_pm_domain.h>
+
+ dphy0: phy@4580000 {
+ compatible = "cdns,dphy-rx";
+ reg = <0x4580000 0x1100>;
+ #phy-cells = <0>;
+ power-domains = <&k3_pds 147 TI_SCI_PD_EXCLUSIVE>;
+ };
--
2.33.1.835.ge9e5ba39a7
Convert Cadence DPHY binding to YAML.
Signed-off-by: Pratyush Yadav <[email protected]>
Reviewed-by: Laurent Pinchart <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
---
(no changes since v3)
Changes in v3:
- Add Rob's R-by.
Changes in v2:
- Drop reg description.
- Add a description for each DPHY clock.
- Rename dphy@... to phy@... in example.
- Add Laurent's R-by.
- Re-order subject prefixes.
.../devicetree/bindings/phy/cdns,dphy.txt | 20 --------
.../devicetree/bindings/phy/cdns,dphy.yaml | 51 +++++++++++++++++++
2 files changed, 51 insertions(+), 20 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy.txt
create mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy.yaml
diff --git a/Documentation/devicetree/bindings/phy/cdns,dphy.txt b/Documentation/devicetree/bindings/phy/cdns,dphy.txt
deleted file mode 100644
index 1095bc4e72d9..000000000000
--- a/Documentation/devicetree/bindings/phy/cdns,dphy.txt
+++ /dev/null
@@ -1,20 +0,0 @@
-Cadence DPHY
-============
-
-Cadence DPHY block.
-
-Required properties:
-- compatible: should be set to "cdns,dphy".
-- reg: physical base address and length of the DPHY registers.
-- clocks: DPHY reference clocks.
-- clock-names: must contain "psm" and "pll_ref".
-- #phy-cells: must be set to 0.
-
-Example:
- dphy0: dphy@fd0e0000{
- compatible = "cdns,dphy";
- reg = <0x0 0xfd0e0000 0x0 0x1000>;
- clocks = <&psm_clk>, <&pll_ref_clk>;
- clock-names = "psm", "pll_ref";
- #phy-cells = <0>;
- };
diff --git a/Documentation/devicetree/bindings/phy/cdns,dphy.yaml b/Documentation/devicetree/bindings/phy/cdns,dphy.yaml
new file mode 100644
index 000000000000..b90a58773bf2
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/cdns,dphy.yaml
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/cdns,dphy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cadence DPHY Device Tree Bindings
+
+maintainers:
+ - Pratyush Yadav <[email protected]>
+
+properties:
+ compatible:
+ items:
+ - const: cdns,dphy
+
+ reg:
+ maxItems: 1
+
+ clocks:
+ items:
+ - description: PMA state machine clock
+ - description: PLL reference clock
+
+ clock-names:
+ items:
+ - const: psm
+ - const: pll_ref
+
+ "#phy-cells":
+ const: 0
+
+required:
+ - compatible
+ - reg
+ - clocks
+ - clock-names
+ - "#phy-cells"
+
+additionalProperties: false
+
+examples:
+ - |
+
+ dphy0: phy@fd0e0000{
+ compatible = "cdns,dphy";
+ reg = <0xfd0e0000 0x1000>;
+ clocks = <&psm_clk>, <&pll_ref_clk>;
+ clock-names = "psm", "pll_ref";
+ #phy-cells = <0>;
+ };
--
2.33.1.835.ge9e5ba39a7
This property is needed on TI platforms to enable the PD of the DPHY
before it can be used.
Signed-off-by: Pratyush Yadav <[email protected]>
Reviewed-by: Laurent Pinchart <[email protected]>
Acked-by: Rob Herring <[email protected]>
---
(no changes since v3)
Changes in v3:
- Add Rob's Ack.
Changes in v2:
- Add power-domain to the example.
- Add Laurent's R-by.
- Re-order subject prefixes.
Documentation/devicetree/bindings/phy/cdns,dphy.yaml | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/Documentation/devicetree/bindings/phy/cdns,dphy.yaml b/Documentation/devicetree/bindings/phy/cdns,dphy.yaml
index b90a58773bf2..c50629bd1b51 100644
--- a/Documentation/devicetree/bindings/phy/cdns,dphy.yaml
+++ b/Documentation/devicetree/bindings/phy/cdns,dphy.yaml
@@ -30,6 +30,9 @@ properties:
"#phy-cells":
const: 0
+ power-domains:
+ maxItems: 1
+
required:
- compatible
- reg
@@ -41,11 +44,13 @@ additionalProperties: false
examples:
- |
+ #include <dt-bindings/soc/ti,sci_pm_domain.h>
dphy0: phy@fd0e0000{
compatible = "cdns,dphy";
reg = <0xfd0e0000 0x1000>;
clocks = <&psm_clk>, <&pll_ref_clk>;
clock-names = "psm", "pll_ref";
+ power-domains = <&k3_pds 147 TI_SCI_PD_EXCLUSIVE>;
#phy-cells = <0>;
};
--
2.33.1.835.ge9e5ba39a7
On Tue, 14 Dec 2021 23:37:03 +0530, Pratyush Yadav wrote:
> The Rx mode DPHY is different from Tx mode DPHY. Add a separate binding
> for it.
>
> Signed-off-by: Pratyush Yadav <[email protected]>
>
> ---
>
> Changes in v6:
> - Add a new binding for DPHY Rx.
>
> .../devicetree/bindings/phy/cdns,dphy-rx.yaml | 42 +++++++++++++++++++
> 1 file changed, 42 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/phy/cdns,dphy-rx.yaml
>
Reviewed-by: Rob Herring <[email protected]>
Hi Pratyush,
On Tue 14 Dec 21, 23:37, Pratyush Yadav wrote:
> The Cadence D-PHY can be configured in Tx (DSI) mode or Rx (CSI) mode.
> Both modes have a different programming sequence and share little among
> them. In addition, a PHY configured in Tx mode cannot be used in Rx mode
> and vice versa. For this reason, create a separate driver for the Rx
> mode to make it easier to read and maintain.
>
> Signed-off-by: Pratyush Yadav <[email protected]>
>
> ---
>
> Changes in v6:
> - Move to a separate driver.
>
> Changes in v5:
> - Use the new cdns_dphy_info to specify PHY ops.
> - Re-order include in alphabetical order.
> - Make bands const.
> - Drop num_bands.
> - Make i, lanes unsigned.
> - Drop the maximum check in cdns_dphy_rx_get_band_ctrl(). Let the loop
> complete and return -EOPNOTSUPP when we reach the end.
> - Drop the "rate < bands[i].min_rate" check since the bands are in
> ascending order.
> - Move data_lane_ctrl to start of function and make it static const.
>
> Changes in v4:
> - Drop the submode parts. Use a different compatible for the Rx ops.
> - Make bands and num_bands static.
>
> Changes in v3:
> - Use a table to select the band.
> - Use a table to poll the data lane ready bits.
> - Multiply the DPHY HS clock rate by 2 to get the bit rate since the
> clock is DDR.
>
> drivers/phy/cadence/Kconfig | 8 +
> drivers/phy/cadence/Makefile | 1 +
> drivers/phy/cadence/cdns-dphy-rx.c | 250 +++++++++++++++++++++++++++++
> 3 files changed, 259 insertions(+)
> create mode 100644 drivers/phy/cadence/cdns-dphy-rx.c
>
> diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
> index a62910ff5591..1adde2d99ae7 100644
> --- a/drivers/phy/cadence/Kconfig
> +++ b/drivers/phy/cadence/Kconfig
> @@ -22,6 +22,14 @@ config PHY_CADENCE_DPHY
> system. If M is selected, the module will be called
> cdns-dphy.
>
> +config PHY_CADENCE_DPHY_RX
> + tristate "Cadence D-PHY Rx Support"
> + depends on HAS_IOMEM && OF
> + select GENERIC_PHY
> + select GENERIC_PHY_MIPI_DPHY
> + help
> + Support for Cadence D-PHY in Rx configuration.
> +
> config PHY_CADENCE_SIERRA
> tristate "Cadence Sierra PHY Driver"
> depends on OF && HAS_IOMEM && RESET_CONTROLLER
> diff --git a/drivers/phy/cadence/Makefile b/drivers/phy/cadence/Makefile
> index 26e16bd34efe..e17f035ddece 100644
> --- a/drivers/phy/cadence/Makefile
> +++ b/drivers/phy/cadence/Makefile
> @@ -1,5 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0-only
> obj-$(CONFIG_PHY_CADENCE_TORRENT) += phy-cadence-torrent.o
> obj-$(CONFIG_PHY_CADENCE_DPHY) += cdns-dphy.o
> +obj-$(CONFIG_PHY_CADENCE_DPHY_RX) += cdns-dphy-rx.o
> obj-$(CONFIG_PHY_CADENCE_SIERRA) += phy-cadence-sierra.o
> obj-$(CONFIG_PHY_CADENCE_SALVO) += phy-cadence-salvo.o
> diff --git a/drivers/phy/cadence/cdns-dphy-rx.c b/drivers/phy/cadence/cdns-dphy-rx.c
> new file mode 100644
> index 000000000000..fb75e645e662
> --- /dev/null
> +++ b/drivers/phy/cadence/cdns-dphy-rx.c
> @@ -0,0 +1,250 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com/
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/module.h>
> +#include <linux/phy/phy.h>
> +#include <linux/phy/phy-mipi-dphy.h>
> +#include <linux/platform_device.h>
> +
> +#define DPHY_PMA_CMN(reg) (reg)
> +#define DPHY_PCS(reg) (0xb00 + (reg))
> +#define DPHY_ISO(reg) (0xc00 + (reg))
> +
> +#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
> +#define DPHY_CMN_RX_MODE_EN BIT(10)
> +#define DPHY_CMN_RX_BANDGAP_TIMER_MASK GENMASK(8, 1)
> +#define DPHY_CMN_SSM_EN BIT(0)
> +
> +#define DPHY_CMN_RX_BANDGAP_TIMER 0x14
> +
> +#define DPHY_BAND_CFG DPHY_PCS(0x0)
> +#define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
> +#define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
> +
> +#define DPHY_POWER_ISLAND_EN_DATA DPHY_PCS(0x8)
> +#define DPHY_POWER_ISLAND_EN_DATA_VAL 0xaaaaaaaa
> +
> +#define DPHY_POWER_ISLAND_EN_CLK DPHY_PCS(0xc)
> +#define DPHY_POWER_ISLAND_EN_CLK_VAL 0xaa
> +
> +#define DPHY_ISO_CL_CTRL_L DPHY_ISO(0x10)
> +#define DPHY_ISO_DL_CTRL_L0 DPHY_ISO(0x14)
> +#define DPHY_ISO_DL_CTRL_L1 DPHY_ISO(0x20)
> +#define DPHY_ISO_DL_CTRL_L2 DPHY_ISO(0x30)
> +#define DPHY_ISO_DL_CTRL_L3 DPHY_ISO(0x3c)
> +
> +#define DPHY_ISO_LANE_READY_BIT 0
> +#define DPHY_ISO_LANE_READY_TIMEOUT_MS 100UL
> +
> +#define DPHY_LANES_MIN 1
> +#define DPHY_LANES_MAX 4
> +
> +struct cdns_dphy_rx {
> + void __iomem *regs;
> + struct device *dev;
> + struct phy *phy;
> +};
> +
> +struct cdns_dphy_rx_band {
> + /* Rates are in Mbps. */
> + unsigned int min_rate;
> + unsigned int max_rate;
> +};
> +
> +/* Order of bands is important since the index is the band number. */
> +static const struct cdns_dphy_rx_band bands[] = {
> + {80, 100}, {100, 120}, {120, 160}, {160, 200}, {200, 240},
> + {240, 280}, {280, 320}, {320, 360}, {360, 400}, {400, 480},
> + {480, 560}, {560, 640}, {640, 720}, {720, 800}, {800, 880},
> + {880, 1040}, {1040, 1200}, {1200, 1350}, {1350, 1500}, {1500, 1750},
> + {1750, 2000}, {2000, 2250}, {2250, 2500}
Cosmetic suggestion: add whitespaces after { and before }.
> +};
> +
> +static int cdns_dphy_rx_power_on(struct phy *phy)
> +{
> + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> +
> + /* Start RX state machine. */
> + writel(DPHY_CMN_SSM_EN | DPHY_CMN_RX_MODE_EN |
> + FIELD_PREP(DPHY_CMN_RX_BANDGAP_TIMER_MASK,
> + DPHY_CMN_RX_BANDGAP_TIMER),
> + dphy->regs + DPHY_CMN_SSM);
> +
> + return 0;
> +}
> +
> +static int cdns_dphy_rx_power_off(struct phy *phy)
> +{
> + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> +
> + writel(0, dphy->regs + DPHY_CMN_SSM);
> +
> + return 0;
> +}
> +
> +static int cdns_dphy_rx_get_band_ctrl(unsigned long hs_clk_rate)
> +{
> + unsigned int rate, i;
> +
> + rate = hs_clk_rate / 1000000UL;
> + /* Since CSI-2 clock is DDR, the bit rate is twice the clock rate. */
> + rate *= 2;
> +
> + if (rate < bands[0].min_rate)
> + return -EOPNOTSUPP;
> +
> + for (i = 0; i < ARRAY_SIZE(bands); i++) {
> + if (rate < bands[i].max_rate)
> + return i;
> + }
Comstic: you don't need the wrapping { and } here.
> +
> + return -EOPNOTSUPP;
> +}
> +
> +static int cdns_dphy_rx_wait_for_bit(void __iomem *addr, unsigned int bit)
You can probably inline this one.
> +{
> + u32 val;
> +
> + return readl_relaxed_poll_timeout(addr, val, val & BIT(bit), 10,
> + DPHY_ISO_LANE_READY_TIMEOUT_MS * 1000);
> +}
> +
> +static int cdns_dphy_rx_wait_lane_ready(struct cdns_dphy_rx *dphy,
> + unsigned int lanes)
> +{
> + static const u32 data_lane_ctrl[] = {DPHY_ISO_DL_CTRL_L0,
> + DPHY_ISO_DL_CTRL_L1,
> + DPHY_ISO_DL_CTRL_L2,
> + DPHY_ISO_DL_CTRL_L3};
> + void __iomem *reg = dphy->regs;
> + unsigned int i;
> + int ret;
> +
> + /* Data lanes. Minimum one lane is mandatory. */
> + if (lanes < DPHY_LANES_MIN || lanes > DPHY_LANES_MAX)
> + return -EINVAL;
> +
> + /* Clock lane */
> + ret = cdns_dphy_rx_wait_for_bit(reg + DPHY_ISO_CL_CTRL_L,
> + DPHY_ISO_LANE_READY_BIT);
> + if (ret)
> + return ret;
> +
> + for (i = 0; i < lanes; i++) {
> + ret = cdns_dphy_rx_wait_for_bit(reg + data_lane_ctrl[i],
> + DPHY_ISO_LANE_READY_BIT);
> + if (ret)
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int cdns_dphy_rx_configure(struct phy *phy,
> + union phy_configure_opts *opts)
> +{
> + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> + unsigned int reg;
> + int band_ctrl, ret;
> +
> + band_ctrl = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
> + if (band_ctrl < 0)
> + return band_ctrl;
> +
> + reg = FIELD_PREP(DPHY_BAND_CFG_LEFT_BAND, band_ctrl) |
> + FIELD_PREP(DPHY_BAND_CFG_RIGHT_BAND, band_ctrl);
> + writel(reg, dphy->regs + DPHY_BAND_CFG);
> +
> + /*
> + * Set the required power island phase 2 time. This is mandated by DPHY
> + * specs.
> + */
> + reg = DPHY_POWER_ISLAND_EN_DATA_VAL;
> + writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_DATA);
> + reg = DPHY_POWER_ISLAND_EN_CLK_VAL;
> + writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_CLK);
> +
> + ret = cdns_dphy_rx_wait_lane_ready(dphy, opts->mipi_dphy.lanes);
> + if (ret) {
> + dev_err(dphy->dev, "DPHY wait for lane ready timeout\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int cdns_dphy_rx_validate(struct phy *phy, enum phy_mode mode,
> + int submode, union phy_configure_opts *opts)
> +{
> + int ret;
> +
> + if (mode != PHY_MODE_MIPI_DPHY)
> + return -EINVAL;
> +
> + ret = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
> + if (ret < 0)
> + return ret;
> +
> + return phy_mipi_dphy_config_validate(&opts->mipi_dphy);
> +}
> +
> +static const struct phy_ops cdns_dphy_rx_ops = {
> + .power_on = cdns_dphy_rx_power_on,
> + .power_off = cdns_dphy_rx_power_off,
> + .configure = cdns_dphy_rx_configure,
> + .validate = cdns_dphy_rx_validate,
> +};
> +
> +static int cdns_dphy_rx_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct phy_provider *provider;
> + struct cdns_dphy_rx *dphy;
> +
> + dphy = devm_kzalloc(dev, sizeof(*dphy), GFP_KERNEL);
> + if (!dphy)
> + return -ENOMEM;
> +
> + dev_set_drvdata(dev, dphy);
It looks like you're never getting the dphy pointer from dev so this seems a bit
pointless.
> + dphy->dev = dev;
> +
> + dphy->regs = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(dphy->regs))
> + return PTR_ERR(dphy->regs);
> +
> + dphy->phy = devm_phy_create(dev, NULL, &cdns_dphy_rx_ops);
> + if (IS_ERR(dphy->phy)) {
> + dev_err(dev, "Failed to create PHY: %d\n", PTR_ERR(dphy->phy));
> + return PTR_ERR(dphy->phy);
> + }
> +
> + phy_set_drvdata(dphy->phy, dphy);
> + provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
You might want to print an error message if it failed to register.
> +
> + return PTR_ERR_OR_ZERO(provider);
> +}
> +
> +static const struct of_device_id cdns_dphy_rx_of_match[] = {
> + { .compatible = "cdns,dphy-rx" },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, cdns_dphy_rx_of_match);
> +
> +static struct platform_driver cdns_dphy_rx_platform_driver = {
> + .probe = cdns_dphy_rx_probe,
> + .driver = {
> + .name = "cdns-mipi-dphy-rx",
> + .of_match_table = cdns_dphy_rx_of_match,
> + },
> +};
> +module_platform_driver(cdns_dphy_rx_platform_driver);
> +
> +MODULE_AUTHOR("Pratyush Yadav <[email protected]>");
> +MODULE_DESCRIPTION("Cadence D-PHY Rx Driver");
> +MODULE_LICENSE("GPL v2");
Otherwise this looks good to me!
Cheers,
Paul
--
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com
On 20/12/21 04:31PM, Paul Kocialkowski wrote:
> Hi Pratyush,
>
> On Tue 14 Dec 21, 23:37, Pratyush Yadav wrote:
> > The Cadence D-PHY can be configured in Tx (DSI) mode or Rx (CSI) mode.
> > Both modes have a different programming sequence and share little among
> > them. In addition, a PHY configured in Tx mode cannot be used in Rx mode
> > and vice versa. For this reason, create a separate driver for the Rx
> > mode to make it easier to read and maintain.
> >
> > Signed-off-by: Pratyush Yadav <[email protected]>
> >
> > ---
> >
> > Changes in v6:
> > - Move to a separate driver.
> >
> > Changes in v5:
> > - Use the new cdns_dphy_info to specify PHY ops.
> > - Re-order include in alphabetical order.
> > - Make bands const.
> > - Drop num_bands.
> > - Make i, lanes unsigned.
> > - Drop the maximum check in cdns_dphy_rx_get_band_ctrl(). Let the loop
> > complete and return -EOPNOTSUPP when we reach the end.
> > - Drop the "rate < bands[i].min_rate" check since the bands are in
> > ascending order.
> > - Move data_lane_ctrl to start of function and make it static const.
> >
> > Changes in v4:
> > - Drop the submode parts. Use a different compatible for the Rx ops.
> > - Make bands and num_bands static.
> >
> > Changes in v3:
> > - Use a table to select the band.
> > - Use a table to poll the data lane ready bits.
> > - Multiply the DPHY HS clock rate by 2 to get the bit rate since the
> > clock is DDR.
> >
> > drivers/phy/cadence/Kconfig | 8 +
> > drivers/phy/cadence/Makefile | 1 +
> > drivers/phy/cadence/cdns-dphy-rx.c | 250 +++++++++++++++++++++++++++++
> > 3 files changed, 259 insertions(+)
> > create mode 100644 drivers/phy/cadence/cdns-dphy-rx.c
> >
> > diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
> > index a62910ff5591..1adde2d99ae7 100644
> > --- a/drivers/phy/cadence/Kconfig
> > +++ b/drivers/phy/cadence/Kconfig
> > @@ -22,6 +22,14 @@ config PHY_CADENCE_DPHY
> > system. If M is selected, the module will be called
> > cdns-dphy.
> >
> > +config PHY_CADENCE_DPHY_RX
> > + tristate "Cadence D-PHY Rx Support"
> > + depends on HAS_IOMEM && OF
> > + select GENERIC_PHY
> > + select GENERIC_PHY_MIPI_DPHY
> > + help
> > + Support for Cadence D-PHY in Rx configuration.
> > +
> > config PHY_CADENCE_SIERRA
> > tristate "Cadence Sierra PHY Driver"
> > depends on OF && HAS_IOMEM && RESET_CONTROLLER
> > diff --git a/drivers/phy/cadence/Makefile b/drivers/phy/cadence/Makefile
> > index 26e16bd34efe..e17f035ddece 100644
> > --- a/drivers/phy/cadence/Makefile
> > +++ b/drivers/phy/cadence/Makefile
> > @@ -1,5 +1,6 @@
> > # SPDX-License-Identifier: GPL-2.0-only
> > obj-$(CONFIG_PHY_CADENCE_TORRENT) += phy-cadence-torrent.o
> > obj-$(CONFIG_PHY_CADENCE_DPHY) += cdns-dphy.o
> > +obj-$(CONFIG_PHY_CADENCE_DPHY_RX) += cdns-dphy-rx.o
> > obj-$(CONFIG_PHY_CADENCE_SIERRA) += phy-cadence-sierra.o
> > obj-$(CONFIG_PHY_CADENCE_SALVO) += phy-cadence-salvo.o
> > diff --git a/drivers/phy/cadence/cdns-dphy-rx.c b/drivers/phy/cadence/cdns-dphy-rx.c
> > new file mode 100644
> > index 000000000000..fb75e645e662
> > --- /dev/null
> > +++ b/drivers/phy/cadence/cdns-dphy-rx.c
> > @@ -0,0 +1,250 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com/
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/bitops.h>
> > +#include <linux/io.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/module.h>
> > +#include <linux/phy/phy.h>
> > +#include <linux/phy/phy-mipi-dphy.h>
> > +#include <linux/platform_device.h>
> > +
> > +#define DPHY_PMA_CMN(reg) (reg)
> > +#define DPHY_PCS(reg) (0xb00 + (reg))
> > +#define DPHY_ISO(reg) (0xc00 + (reg))
> > +
> > +#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
> > +#define DPHY_CMN_RX_MODE_EN BIT(10)
> > +#define DPHY_CMN_RX_BANDGAP_TIMER_MASK GENMASK(8, 1)
> > +#define DPHY_CMN_SSM_EN BIT(0)
> > +
> > +#define DPHY_CMN_RX_BANDGAP_TIMER 0x14
> > +
> > +#define DPHY_BAND_CFG DPHY_PCS(0x0)
> > +#define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
> > +#define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
> > +
> > +#define DPHY_POWER_ISLAND_EN_DATA DPHY_PCS(0x8)
> > +#define DPHY_POWER_ISLAND_EN_DATA_VAL 0xaaaaaaaa
> > +
> > +#define DPHY_POWER_ISLAND_EN_CLK DPHY_PCS(0xc)
> > +#define DPHY_POWER_ISLAND_EN_CLK_VAL 0xaa
> > +
> > +#define DPHY_ISO_CL_CTRL_L DPHY_ISO(0x10)
> > +#define DPHY_ISO_DL_CTRL_L0 DPHY_ISO(0x14)
> > +#define DPHY_ISO_DL_CTRL_L1 DPHY_ISO(0x20)
> > +#define DPHY_ISO_DL_CTRL_L2 DPHY_ISO(0x30)
> > +#define DPHY_ISO_DL_CTRL_L3 DPHY_ISO(0x3c)
> > +
> > +#define DPHY_ISO_LANE_READY_BIT 0
> > +#define DPHY_ISO_LANE_READY_TIMEOUT_MS 100UL
> > +
> > +#define DPHY_LANES_MIN 1
> > +#define DPHY_LANES_MAX 4
> > +
> > +struct cdns_dphy_rx {
> > + void __iomem *regs;
> > + struct device *dev;
> > + struct phy *phy;
> > +};
> > +
> > +struct cdns_dphy_rx_band {
> > + /* Rates are in Mbps. */
> > + unsigned int min_rate;
> > + unsigned int max_rate;
> > +};
> > +
> > +/* Order of bands is important since the index is the band number. */
> > +static const struct cdns_dphy_rx_band bands[] = {
> > + {80, 100}, {100, 120}, {120, 160}, {160, 200}, {200, 240},
> > + {240, 280}, {280, 320}, {320, 360}, {360, 400}, {400, 480},
> > + {480, 560}, {560, 640}, {640, 720}, {720, 800}, {800, 880},
> > + {880, 1040}, {1040, 1200}, {1200, 1350}, {1350, 1500}, {1500, 1750},
> > + {1750, 2000}, {2000, 2250}, {2250, 2500}
>
> Cosmetic suggestion: add whitespaces after { and before }.
I think it would just add noise. I would like to keep it compact.
>
> > +};
> > +
> > +static int cdns_dphy_rx_power_on(struct phy *phy)
> > +{
> > + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> > +
> > + /* Start RX state machine. */
> > + writel(DPHY_CMN_SSM_EN | DPHY_CMN_RX_MODE_EN |
> > + FIELD_PREP(DPHY_CMN_RX_BANDGAP_TIMER_MASK,
> > + DPHY_CMN_RX_BANDGAP_TIMER),
> > + dphy->regs + DPHY_CMN_SSM);
> > +
> > + return 0;
> > +}
> > +
> > +static int cdns_dphy_rx_power_off(struct phy *phy)
> > +{
> > + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> > +
> > + writel(0, dphy->regs + DPHY_CMN_SSM);
> > +
> > + return 0;
> > +}
> > +
> > +static int cdns_dphy_rx_get_band_ctrl(unsigned long hs_clk_rate)
> > +{
> > + unsigned int rate, i;
> > +
> > + rate = hs_clk_rate / 1000000UL;
> > + /* Since CSI-2 clock is DDR, the bit rate is twice the clock rate. */
> > + rate *= 2;
> > +
> > + if (rate < bands[0].min_rate)
> > + return -EOPNOTSUPP;
> > +
> > + for (i = 0; i < ARRAY_SIZE(bands); i++) {
> > + if (rate < bands[i].max_rate)
> > + return i;
> > + }
>
> Comstic: you don't need the wrapping { and } here.
Yes, but I generally like to add it for cases like this to make the
scope clearer. But I have no strong preferences, I can drop them.
>
> > +
> > + return -EOPNOTSUPP;
> > +}
> > +
> > +static int cdns_dphy_rx_wait_for_bit(void __iomem *addr, unsigned int bit)
>
> You can probably inline this one.
The compiler will likely do it anyway, but sure I will add it.
>
> > +{
> > + u32 val;
> > +
> > + return readl_relaxed_poll_timeout(addr, val, val & BIT(bit), 10,
> > + DPHY_ISO_LANE_READY_TIMEOUT_MS * 1000);
> > +}
> > +
> > +static int cdns_dphy_rx_wait_lane_ready(struct cdns_dphy_rx *dphy,
> > + unsigned int lanes)
> > +{
> > + static const u32 data_lane_ctrl[] = {DPHY_ISO_DL_CTRL_L0,
> > + DPHY_ISO_DL_CTRL_L1,
> > + DPHY_ISO_DL_CTRL_L2,
> > + DPHY_ISO_DL_CTRL_L3};
> > + void __iomem *reg = dphy->regs;
> > + unsigned int i;
> > + int ret;
> > +
> > + /* Data lanes. Minimum one lane is mandatory. */
> > + if (lanes < DPHY_LANES_MIN || lanes > DPHY_LANES_MAX)
> > + return -EINVAL;
> > +
> > + /* Clock lane */
> > + ret = cdns_dphy_rx_wait_for_bit(reg + DPHY_ISO_CL_CTRL_L,
> > + DPHY_ISO_LANE_READY_BIT);
> > + if (ret)
> > + return ret;
> > +
> > + for (i = 0; i < lanes; i++) {
> > + ret = cdns_dphy_rx_wait_for_bit(reg + data_lane_ctrl[i],
> > + DPHY_ISO_LANE_READY_BIT);
> > + if (ret)
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int cdns_dphy_rx_configure(struct phy *phy,
> > + union phy_configure_opts *opts)
> > +{
> > + struct cdns_dphy_rx *dphy = phy_get_drvdata(phy);
> > + unsigned int reg;
> > + int band_ctrl, ret;
> > +
> > + band_ctrl = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
> > + if (band_ctrl < 0)
> > + return band_ctrl;
> > +
> > + reg = FIELD_PREP(DPHY_BAND_CFG_LEFT_BAND, band_ctrl) |
> > + FIELD_PREP(DPHY_BAND_CFG_RIGHT_BAND, band_ctrl);
> > + writel(reg, dphy->regs + DPHY_BAND_CFG);
> > +
> > + /*
> > + * Set the required power island phase 2 time. This is mandated by DPHY
> > + * specs.
> > + */
> > + reg = DPHY_POWER_ISLAND_EN_DATA_VAL;
> > + writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_DATA);
> > + reg = DPHY_POWER_ISLAND_EN_CLK_VAL;
> > + writel(reg, dphy->regs + DPHY_POWER_ISLAND_EN_CLK);
> > +
> > + ret = cdns_dphy_rx_wait_lane_ready(dphy, opts->mipi_dphy.lanes);
> > + if (ret) {
> > + dev_err(dphy->dev, "DPHY wait for lane ready timeout\n");
> > + return ret;
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int cdns_dphy_rx_validate(struct phy *phy, enum phy_mode mode,
> > + int submode, union phy_configure_opts *opts)
> > +{
> > + int ret;
> > +
> > + if (mode != PHY_MODE_MIPI_DPHY)
> > + return -EINVAL;
> > +
> > + ret = cdns_dphy_rx_get_band_ctrl(opts->mipi_dphy.hs_clk_rate);
> > + if (ret < 0)
> > + return ret;
> > +
> > + return phy_mipi_dphy_config_validate(&opts->mipi_dphy);
> > +}
> > +
> > +static const struct phy_ops cdns_dphy_rx_ops = {
> > + .power_on = cdns_dphy_rx_power_on,
> > + .power_off = cdns_dphy_rx_power_off,
> > + .configure = cdns_dphy_rx_configure,
> > + .validate = cdns_dphy_rx_validate,
> > +};
> > +
> > +static int cdns_dphy_rx_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct phy_provider *provider;
> > + struct cdns_dphy_rx *dphy;
> > +
> > + dphy = devm_kzalloc(dev, sizeof(*dphy), GFP_KERNEL);
> > + if (!dphy)
> > + return -ENOMEM;
> > +
> > + dev_set_drvdata(dev, dphy);
>
> It looks like you're never getting the dphy pointer from dev so this seems a bit
> pointless.
Yes, we don't need it since there is no remove hook as of now. But I
would still like to keep it. It would avoid extra churn when someone
does want to add one.
>
> > + dphy->dev = dev;
> > +
> > + dphy->regs = devm_platform_ioremap_resource(pdev, 0);
> > + if (IS_ERR(dphy->regs))
> > + return PTR_ERR(dphy->regs);
> > +
> > + dphy->phy = devm_phy_create(dev, NULL, &cdns_dphy_rx_ops);
> > + if (IS_ERR(dphy->phy)) {
> > + dev_err(dev, "Failed to create PHY: %d\n", PTR_ERR(dphy->phy));
> > + return PTR_ERR(dphy->phy);
> > + }
> > +
> > + phy_set_drvdata(dphy->phy, dphy);
> > + provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
>
> You might want to print an error message if it failed to register.
Ok, will do.
>
> > +
> > + return PTR_ERR_OR_ZERO(provider);
> > +}
> > +
> > +static const struct of_device_id cdns_dphy_rx_of_match[] = {
> > + { .compatible = "cdns,dphy-rx" },
> > + { /* sentinel */ },
> > +};
> > +MODULE_DEVICE_TABLE(of, cdns_dphy_rx_of_match);
> > +
> > +static struct platform_driver cdns_dphy_rx_platform_driver = {
> > + .probe = cdns_dphy_rx_probe,
> > + .driver = {
> > + .name = "cdns-mipi-dphy-rx",
> > + .of_match_table = cdns_dphy_rx_of_match,
> > + },
> > +};
> > +module_platform_driver(cdns_dphy_rx_platform_driver);
> > +
> > +MODULE_AUTHOR("Pratyush Yadav <[email protected]>");
> > +MODULE_DESCRIPTION("Cadence D-PHY Rx Driver");
> > +MODULE_LICENSE("GPL v2");
>
> Otherwise this looks good to me!
Thanks for reviewing.
>
> Cheers,
>
> Paul
>
> --
> Paul Kocialkowski, Bootlin
> Embedded Linux and kernel engineering
> https://bootlin.com
--
Regards,
Pratyush Yadav
Texas Instruments Inc.
On 23-12-21, 00:15, Pratyush Yadav wrote:
> On 20/12/21 04:31PM, Paul Kocialkowski wrote:
> > Hi Pratyush,
> >
> > On Tue 14 Dec 21, 23:37, Pratyush Yadav wrote:
> > > The Cadence D-PHY can be configured in Tx (DSI) mode or Rx (CSI) mode.
> > > Both modes have a different programming sequence and share little among
> > > them. In addition, a PHY configured in Tx mode cannot be used in Rx mode
> > > and vice versa. For this reason, create a separate driver for the Rx
> > > mode to make it easier to read and maintain.
> > >
> > > Signed-off-by: Pratyush Yadav <[email protected]>
> > >
> > > ---
> > >
> > > Changes in v6:
> > > - Move to a separate driver.
> > >
> > > Changes in v5:
> > > - Use the new cdns_dphy_info to specify PHY ops.
> > > - Re-order include in alphabetical order.
> > > - Make bands const.
> > > - Drop num_bands.
> > > - Make i, lanes unsigned.
> > > - Drop the maximum check in cdns_dphy_rx_get_band_ctrl(). Let the loop
> > > complete and return -EOPNOTSUPP when we reach the end.
> > > - Drop the "rate < bands[i].min_rate" check since the bands are in
> > > ascending order.
> > > - Move data_lane_ctrl to start of function and make it static const.
> > >
> > > Changes in v4:
> > > - Drop the submode parts. Use a different compatible for the Rx ops.
> > > - Make bands and num_bands static.
> > >
> > > Changes in v3:
> > > - Use a table to select the band.
> > > - Use a table to poll the data lane ready bits.
> > > - Multiply the DPHY HS clock rate by 2 to get the bit rate since the
> > > clock is DDR.
> > >
> > > drivers/phy/cadence/Kconfig | 8 +
> > > drivers/phy/cadence/Makefile | 1 +
> > > drivers/phy/cadence/cdns-dphy-rx.c | 250 +++++++++++++++++++++++++++++
> > > 3 files changed, 259 insertions(+)
> > > create mode 100644 drivers/phy/cadence/cdns-dphy-rx.c
> > >
> > > diff --git a/drivers/phy/cadence/Kconfig b/drivers/phy/cadence/Kconfig
> > > index a62910ff5591..1adde2d99ae7 100644
> > > --- a/drivers/phy/cadence/Kconfig
> > > +++ b/drivers/phy/cadence/Kconfig
> > > @@ -22,6 +22,14 @@ config PHY_CADENCE_DPHY
> > > system. If M is selected, the module will be called
> > > cdns-dphy.
> > >
> > > +config PHY_CADENCE_DPHY_RX
> > > + tristate "Cadence D-PHY Rx Support"
> > > + depends on HAS_IOMEM && OF
> > > + select GENERIC_PHY
> > > + select GENERIC_PHY_MIPI_DPHY
> > > + help
> > > + Support for Cadence D-PHY in Rx configuration.
> > > +
> > > config PHY_CADENCE_SIERRA
> > > tristate "Cadence Sierra PHY Driver"
> > > depends on OF && HAS_IOMEM && RESET_CONTROLLER
> > > diff --git a/drivers/phy/cadence/Makefile b/drivers/phy/cadence/Makefile
> > > index 26e16bd34efe..e17f035ddece 100644
> > > --- a/drivers/phy/cadence/Makefile
> > > +++ b/drivers/phy/cadence/Makefile
> > > @@ -1,5 +1,6 @@
> > > # SPDX-License-Identifier: GPL-2.0-only
> > > obj-$(CONFIG_PHY_CADENCE_TORRENT) += phy-cadence-torrent.o
> > > obj-$(CONFIG_PHY_CADENCE_DPHY) += cdns-dphy.o
> > > +obj-$(CONFIG_PHY_CADENCE_DPHY_RX) += cdns-dphy-rx.o
> > > obj-$(CONFIG_PHY_CADENCE_SIERRA) += phy-cadence-sierra.o
> > > obj-$(CONFIG_PHY_CADENCE_SALVO) += phy-cadence-salvo.o
> > > diff --git a/drivers/phy/cadence/cdns-dphy-rx.c b/drivers/phy/cadence/cdns-dphy-rx.c
> > > new file mode 100644
> > > index 000000000000..fb75e645e662
> > > --- /dev/null
> > > +++ b/drivers/phy/cadence/cdns-dphy-rx.c
> > > @@ -0,0 +1,250 @@
> > > +// SPDX-License-Identifier: GPL-2.0+
> > > +/*
> > > + * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com/
> > > + */
> > > +
> > > +#include <linux/bitfield.h>
> > > +#include <linux/bitops.h>
> > > +#include <linux/io.h>
> > > +#include <linux/iopoll.h>
> > > +#include <linux/module.h>
> > > +#include <linux/phy/phy.h>
> > > +#include <linux/phy/phy-mipi-dphy.h>
> > > +#include <linux/platform_device.h>
> > > +
> > > +#define DPHY_PMA_CMN(reg) (reg)
> > > +#define DPHY_PCS(reg) (0xb00 + (reg))
> > > +#define DPHY_ISO(reg) (0xc00 + (reg))
> > > +
> > > +#define DPHY_CMN_SSM DPHY_PMA_CMN(0x20)
> > > +#define DPHY_CMN_RX_MODE_EN BIT(10)
> > > +#define DPHY_CMN_RX_BANDGAP_TIMER_MASK GENMASK(8, 1)
> > > +#define DPHY_CMN_SSM_EN BIT(0)
> > > +
> > > +#define DPHY_CMN_RX_BANDGAP_TIMER 0x14
> > > +
> > > +#define DPHY_BAND_CFG DPHY_PCS(0x0)
> > > +#define DPHY_BAND_CFG_RIGHT_BAND GENMASK(9, 5)
> > > +#define DPHY_BAND_CFG_LEFT_BAND GENMASK(4, 0)
> > > +
> > > +#define DPHY_POWER_ISLAND_EN_DATA DPHY_PCS(0x8)
> > > +#define DPHY_POWER_ISLAND_EN_DATA_VAL 0xaaaaaaaa
> > > +
> > > +#define DPHY_POWER_ISLAND_EN_CLK DPHY_PCS(0xc)
> > > +#define DPHY_POWER_ISLAND_EN_CLK_VAL 0xaa
> > > +
> > > +#define DPHY_ISO_CL_CTRL_L DPHY_ISO(0x10)
> > > +#define DPHY_ISO_DL_CTRL_L0 DPHY_ISO(0x14)
> > > +#define DPHY_ISO_DL_CTRL_L1 DPHY_ISO(0x20)
> > > +#define DPHY_ISO_DL_CTRL_L2 DPHY_ISO(0x30)
> > > +#define DPHY_ISO_DL_CTRL_L3 DPHY_ISO(0x3c)
> > > +
> > > +#define DPHY_ISO_LANE_READY_BIT 0
> > > +#define DPHY_ISO_LANE_READY_TIMEOUT_MS 100UL
> > > +
> > > +#define DPHY_LANES_MIN 1
> > > +#define DPHY_LANES_MAX 4
> > > +
> > > +struct cdns_dphy_rx {
> > > + void __iomem *regs;
> > > + struct device *dev;
> > > + struct phy *phy;
> > > +};
> > > +
> > > +struct cdns_dphy_rx_band {
> > > + /* Rates are in Mbps. */
> > > + unsigned int min_rate;
> > > + unsigned int max_rate;
> > > +};
> > > +
> > > +/* Order of bands is important since the index is the band number. */
> > > +static const struct cdns_dphy_rx_band bands[] = {
> > > + {80, 100}, {100, 120}, {120, 160}, {160, 200}, {200, 240},
> > > + {240, 280}, {280, 320}, {320, 360}, {360, 400}, {400, 480},
> > > + {480, 560}, {560, 640}, {640, 720}, {720, 800}, {800, 880},
> > > + {880, 1040}, {1040, 1200}, {1200, 1350}, {1350, 1500}, {1500, 1750},
> > > + {1750, 2000}, {2000, 2250}, {2250, 2500}
> >
> > Cosmetic suggestion: add whitespaces after { and before }.
>
> I think it would just add noise. I would like to keep it compact.
No, it makes it look lot more neater and is usually the convention
followed in kernel
--
~Vinod