This driver adds support to perform calibration of the MIPI pads for CSI
and DSI.
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
---
Changes in v3:
- add device tree binding documentation
Changes in v2:
- rename fields to mirror the names in the TRM
- remove unused fields
.../bindings/misc/nvidia,tegra114-mipi.txt | 37 ++++
drivers/gpu/host1x/Makefile | 1 +
drivers/gpu/host1x/dev.c | 17 +-
drivers/gpu/host1x/dev.h | 2 +
drivers/gpu/host1x/mipi.c | 230 +++++++++++++++++++++
include/linux/host1x.h | 2 +
6 files changed, 285 insertions(+), 4 deletions(-)
create mode 100644 Documentation/devicetree/bindings/misc/nvidia,tegra114-mipi.txt
create mode 100644 drivers/gpu/host1x/mipi.c
diff --git a/Documentation/devicetree/bindings/misc/nvidia,tegra114-mipi.txt b/Documentation/devicetree/bindings/misc/nvidia,tegra114-mipi.txt
new file mode 100644
index 0000000..642c5d8
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/nvidia,tegra114-mipi.txt
@@ -0,0 +1,37 @@
+NVIDIA Tegra MIPI pad calibration controller
+
+Required properties:
+- compatible: "nvidia,tegra<chip>-mipi"
+- reg: Physical base address and length of the controller's registers.
+- clocks: The clock consumed by the controller.
+- #calibrate-cells: Should be 1. The cell is a bitmask of the pads that need
+ to be calibrated by a given device.
+
+User nodes need to contain a calibrate property that has a phandle to refer
+to the calibration controller node and a bitmask of the pads that need to be
+calibrated.
+
+Example:
+
+ mipi: mipi@700e3000 {
+ compatible = "nvidia,tegra114-mipi";
+ reg = <0x700e3000 0x100>;
+ clocks = <&tegra_car TEGRA114_CLK_MIPI_CAL>;
+ #calibrate-cells = <1>;
+ };
+
+ ...
+
+ host1x@50000000 {
+ ...
+
+ dsi@54300000 {
+ ...
+
+ calibrate = <&mipi 0x060>;
+
+ ...
+ };
+
+ ...
+ };
diff --git a/drivers/gpu/host1x/Makefile b/drivers/gpu/host1x/Makefile
index afa1e9e..de305c2 100644
--- a/drivers/gpu/host1x/Makefile
+++ b/drivers/gpu/host1x/Makefile
@@ -7,6 +7,7 @@ host1x-y = \
channel.o \
job.o \
debug.o \
+ mipi.o \
hw/host1x01.o \
hw/host1x02.o
diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
index ab402a5..12d6333 100644
--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -208,17 +208,26 @@ static int __init tegra_host1x_init(void)
return err;
err = platform_driver_register(&tegra_host1x_driver);
- if (err < 0) {
- host1x_bus_exit();
- return err;
- }
+ if (err < 0)
+ goto unregister_bus;
+
+ err = platform_driver_register(&tegra_mipi_driver);
+ if (err < 0)
+ goto unregister_host1x;
return 0;
+
+unregister_host1x:
+ platform_driver_unregister(&tegra_host1x_driver);
+unregister_bus:
+ host1x_bus_exit();
+ return err;
}
module_init(tegra_host1x_init);
static void __exit tegra_host1x_exit(void)
{
+ platform_driver_unregister(&tegra_mipi_driver);
platform_driver_unregister(&tegra_host1x_driver);
host1x_bus_exit();
}
diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h
index 6cf689b..65c80dc 100644
--- a/drivers/gpu/host1x/dev.h
+++ b/drivers/gpu/host1x/dev.h
@@ -304,4 +304,6 @@ static inline void host1x_hw_show_mlocks(struct host1x *host, struct output *o)
host->debug_op->show_mlocks(host, o);
}
+extern struct platform_driver tegra_mipi_driver;
+
#endif
diff --git a/drivers/gpu/host1x/mipi.c b/drivers/gpu/host1x/mipi.c
new file mode 100644
index 0000000..8a54613
--- /dev/null
+++ b/drivers/gpu/host1x/mipi.c
@@ -0,0 +1,230 @@
+/*
+ * Copyright (C) 2013 NVIDIA Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define MIPI_CAL_CTRL 0x00
+#define MIPI_CAL_CTRL_START (1 << 0)
+
+#define MIPI_CAL_AUTOCAL_CTRL 0x01
+
+#define MIPI_CAL_STATUS 0x02
+#define MIPI_CAL_STATUS_DONE (1 << 16)
+#define MIPI_CAL_STATUS_ACTIVE (1 << 0)
+
+#define MIPI_CAL_CONFIG_CSIA 0x05
+#define MIPI_CAL_CONFIG_CSIB 0x06
+#define MIPI_CAL_CONFIG_CSIC 0x07
+#define MIPI_CAL_CONFIG_CSID 0x08
+#define MIPI_CAL_CONFIG_CSIE 0x09
+#define MIPI_CAL_CONFIG_DSIA 0x0e
+#define MIPI_CAL_CONFIG_DSIB 0x0f
+#define MIPI_CAL_CONFIG_DSIC 0x10
+#define MIPI_CAL_CONFIG_DSID 0x11
+
+#define MIPI_CAL_CONFIG_SELECT (1 << 21)
+#define MIPI_CAL_CONFIG_HSPDOS(x) (((x) & 0x1f) << 16)
+#define MIPI_CAL_CONFIG_HSPUOS(x) (((x) & 0x1f) << 8)
+#define MIPI_CAL_CONFIG_TERMOS(x) (((x) & 0x1f) << 0)
+
+#define MIPI_CAL_BIAS_PAD_CFG0 0x16
+#define MIPI_CAL_BIAS_PAD_PDVCLAMP (1 << 1)
+#define MIPI_CAL_BIAS_PAD_E_VCLAMP_REF (1 << 0)
+
+#define MIPI_CAL_BIAS_PAD_CFG1 0x17
+
+#define MIPI_CAL_BIAS_PAD_CFG2 0x18
+#define MIPI_CAL_BIAS_PAD_PDVREG (1 << 1)
+
+static const struct module {
+ unsigned long reg;
+} modules[] = {
+ { .reg = MIPI_CAL_CONFIG_CSIA },
+ { .reg = MIPI_CAL_CONFIG_CSIB },
+ { .reg = MIPI_CAL_CONFIG_CSIC },
+ { .reg = MIPI_CAL_CONFIG_CSID },
+ { .reg = MIPI_CAL_CONFIG_CSIE },
+ { .reg = MIPI_CAL_CONFIG_DSIA },
+ { .reg = MIPI_CAL_CONFIG_DSIB },
+ { .reg = MIPI_CAL_CONFIG_DSIC },
+ { .reg = MIPI_CAL_CONFIG_DSID },
+};
+
+struct tegra_mipi {
+ void __iomem *regs;
+ struct mutex lock;
+ struct clk *clk;
+};
+
+static inline unsigned long tegra_mipi_readl(struct tegra_mipi *mipi,
+ unsigned long reg)
+{
+ return readl(mipi->regs + (reg << 2));
+}
+
+static inline void tegra_mipi_writel(struct tegra_mipi *mipi,
+ unsigned long value, unsigned long reg)
+{
+ writel(value, mipi->regs + (reg << 2));
+}
+
+int tegra_mipi_calibrate(struct device *device)
+{
+ struct platform_device *pdev;
+ unsigned int timeout = 20, i;
+ struct of_phandle_args args;
+ unsigned long value, pads;
+ struct tegra_mipi *mipi;
+ int err;
+
+ err = of_parse_phandle_with_args(device->of_node, "calibrate",
+ "#calibrate-cells", 0, &args);
+ if (err < 0)
+ return err;
+
+ pdev = of_find_device_by_node(args.np);
+ if (!pdev) {
+ of_node_put(args.np);
+ return -ENODEV;
+ }
+
+ of_node_put(args.np);
+ pads = args.args[0];
+
+ mipi = platform_get_drvdata(pdev);
+ if (!mipi) {
+ err = -ENODEV;
+ goto out;
+ }
+
+ err = clk_enable(mipi->clk);
+ if (err < 0)
+ goto out;
+
+ mutex_lock(&mipi->lock);
+
+ value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG0);
+ value &= ~MIPI_CAL_BIAS_PAD_PDVCLAMP;
+ value |= MIPI_CAL_BIAS_PAD_E_VCLAMP_REF;
+ tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG0);
+
+ value = tegra_mipi_readl(mipi, MIPI_CAL_BIAS_PAD_CFG2);
+ value &= ~MIPI_CAL_BIAS_PAD_PDVREG;
+ tegra_mipi_writel(mipi, value, MIPI_CAL_BIAS_PAD_CFG2);
+
+ for (i = 0; i < ARRAY_SIZE(modules); i++) {
+ if (pads & BIT(i))
+ value = MIPI_CAL_CONFIG_SELECT |
+ MIPI_CAL_CONFIG_HSPDOS(0) |
+ MIPI_CAL_CONFIG_HSPUOS(4) |
+ MIPI_CAL_CONFIG_TERMOS(5);
+ else
+ value = 0;
+
+ tegra_mipi_writel(mipi, value, modules[i].reg);
+ }
+
+ tegra_mipi_writel(mipi, MIPI_CAL_CTRL_START, MIPI_CAL_CTRL);
+
+ while (timeout) {
+ value = tegra_mipi_readl(mipi, MIPI_CAL_STATUS);
+ if ((value & MIPI_CAL_STATUS_ACTIVE) == 0 &&
+ (value & MIPI_CAL_STATUS_DONE) != 0)
+ break;
+
+ usleep_range(10, 100);
+ timeout--;
+ }
+
+ mutex_unlock(&mipi->lock);
+ clk_disable(mipi->clk);
+
+ if (timeout == 0)
+ err = -ETIMEDOUT;
+ else
+ err = 0;
+
+out:
+ platform_device_put(pdev);
+ return err;
+}
+EXPORT_SYMBOL_GPL(tegra_mipi_calibrate);
+
+static int tegra_mipi_probe(struct platform_device *pdev)
+{
+ struct tegra_mipi *mipi;
+ struct resource *res;
+ int err;
+
+ mipi = devm_kzalloc(&pdev->dev, sizeof(*mipi), GFP_KERNEL);
+ if (!mipi)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ mipi->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(mipi->regs))
+ return PTR_ERR(mipi->regs);
+
+ mutex_init(&mipi->lock);
+
+ mipi->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(mipi->clk)) {
+ dev_err(&pdev->dev, "failed to get clock\n");
+ return PTR_ERR(mipi->clk);
+ }
+
+ err = clk_prepare(mipi->clk);
+ if (err < 0)
+ return err;
+
+ platform_set_drvdata(pdev, mipi);
+
+ return 0;
+}
+
+static int tegra_mipi_remove(struct platform_device *pdev)
+{
+ struct tegra_mipi *mipi = platform_get_drvdata(pdev);
+
+ clk_unprepare(mipi->clk);
+
+ return 0;
+}
+
+static struct of_device_id tegra_mipi_of_match[] = {
+ { .compatible = "nvidia,tegra114-mipi", },
+ { },
+};
+
+struct platform_driver tegra_mipi_driver = {
+ .driver = {
+ .name = "tegra-mipi",
+ .of_match_table = tegra_mipi_of_match,
+ },
+ .probe = tegra_mipi_probe,
+ .remove = tegra_mipi_remove,
+};
diff --git a/include/linux/host1x.h b/include/linux/host1x.h
index e62c61a..da6dd01 100644
--- a/include/linux/host1x.h
+++ b/include/linux/host1x.h
@@ -273,4 +273,6 @@ int host1x_device_exit(struct host1x_device *device);
int host1x_client_register(struct host1x_client *client);
int host1x_client_unregister(struct host1x_client *client);
+int tegra_mipi_calibrate(struct device *device);
+
#endif
--
1.8.4
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