[RFC v3 3/4] drm/i915: Add new panel driver based on crystal cove pmic

Shobhit Kumar
2015-01-21T11:18:12Z

This driver provides support for the "crystal_cove_panel" cell device.
On BYT-T pmic has to be used to enable/disable panel.

v2: Addressed Jani's comments
- Moved inside i915
- Correct licensing
- Remove unused stuff
- Do not initialize prepare/unprepare as they are not needed as of now
- Correct backlight off delay

Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
---
drivers/gpu/drm/i915/Kconfig | 12 ++
drivers/gpu/drm/i915/Makefile | 3 +
drivers/gpu/drm/i915/intel-panel-crystalcove.c | 159 +++++++++++++++++++++++++
3 files changed, 174 insertions(+)
create mode 100644 drivers/gpu/drm/i915/intel-panel-crystalcove.c

diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig
index 4e39ab3..0510ef0 100644
--- a/drivers/gpu/drm/i915/Kconfig
+++ b/drivers/gpu/drm/i915/Kconfig
@@ -69,3 +69,15 @@ config DRM_I915_PRELIMINARY_HW_SUPPORT
option changes the default for that module option.

If in doubt, say "N".
+
+config DRM_I915_PANEL_CRYSTALCOVE_PMIC
+ bool "Enable drm panel for crystal cove pmic based control"
+ depends on DRM_I915
+ depends on DRM_PANEL
+ default n
+ help
+ Choose this option if you have BYT-T based device with DSI panel. On
+ BYT-T there a crystal cove PMIC which controls the PANEL EN/DISABLE
+ signals.
+
+ If in doubt, say "N".
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index 1849ffa..cc2f10d 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -88,4 +88,7 @@ i915-y += i915_dma.o \

obj-$(CONFIG_DRM_I915) += i915.o

+# I915 DRM Panels
+obj-$(CONFIG_DRM_I915_PANEL_CRYSTALCOVE_PMIC) += intel-panel-crystalcove.o
+
CFLAGS_i915_trace_points.o := -I$(src)
diff --git a/drivers/gpu/drm/i915/intel-panel-crystalcove.c b/drivers/gpu/drm/i915/intel-panel-crystalcove.c
new file mode 100644
index 0000000..a6aefa3
--- /dev/null
+++ b/drivers/gpu/drm/i915/intel-panel-crystalcove.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright © 2014 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Authors:
+ * Shobhit Kumar <shobhit.kumar@intel.com>
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_panel.h>
+#include <linux/mfd/intel_soc_pmic.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define PMIC_PANEL_EN 0x52
+#define PMIC_PWM_EN 0x51
+#define PMIC_BKL_EN 0x4B
+#define PMIC_PWM_LEVEL 0x4E
+
+struct crystalcove_panel {
+ struct drm_panel base;
+ bool enabled;
+
+ /* crystal cove pmic regmap */
+ struct regmap *regmap;
+};
+
+static inline struct crystalcove_panel *to_crystalcove_panel(struct drm_panel *panel)
+{
+ return container_of(panel, struct crystalcove_panel, base);
+}
+
+static int crystalcove_panel_disable(struct drm_panel *panel)
+{
+ struct crystalcove_panel *p = to_crystalcove_panel(panel);
+
+ if (!p->enabled)
+ return 0;
+
+ DRM_DEBUG_KMS("\n");
+
+ /* invoke the pmic driver */
+ regmap_write(p->regmap, PMIC_PANEL_EN, 0x00);
+
+ /* Disable backlight as well */
+ regmap_write(p->regmap, PMIC_PWM_LEVEL, 0);
+ msleep(20);
+ regmap_write(p->regmap, PMIC_PWM_EN, 0x00);
+ regmap_write(p->regmap, PMIC_BKL_EN, 0x7F);
+
+ p->enabled = false;
+
+ return 0;
+}
+
+static int crystalcove_panel_enable(struct drm_panel *panel)
+{
+ struct crystalcove_panel *p = to_crystalcove_panel(panel);
+
+ if (p->enabled)
+ return 0;
+
+ DRM_DEBUG_KMS("\n");
+
+ /* invoke the pmic driver */
+ regmap_write(p->regmap, PMIC_PANEL_EN, 0x01);
+
+ /* Enable BKL as well */
+ regmap_write(p->regmap, PMIC_BKL_EN, 0xFF);
+ regmap_write(p->regmap, PMIC_PWM_EN, 0x01);
+ msleep(20);
+ regmap_write(p->regmap, PMIC_PWM_LEVEL, 255);
+
+ p->enabled = true;
+
+ return 0;
+}
+
+static const struct drm_panel_funcs crystalcove_panel_funcs = {
+ .disable = crystalcove_panel_disable,
+ .enable = crystalcove_panel_enable,
+};
+
+static int crystalcove_panel_probe(struct platform_device *pdev)
+{
+ struct crystalcove_panel *panel;
+ int retval;
+ struct device *dev = pdev->dev.parent;
+ struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
+
+ panel = devm_kzalloc(&pdev->dev, sizeof(*panel), GFP_KERNEL);
+ if (!panel)
+ return -ENOMEM;
+
+ DRM_DEBUG_KMS("\n");
+
+ platform_set_drvdata(pdev, panel);
+
+ strcpy(panel->base.name, "crystal_cove_panel");
+ panel->regmap = pmic->regmap;
+
+ regmap_read(panel->regmap, PMIC_PANEL_EN, &retval);
+ panel->enabled = retval;
+
+ drm_panel_init(&panel->base);
+ panel->base.dev = dev;
+ panel->base.funcs = &crystalcove_panel_funcs;
+
+ drm_panel_add(&panel->base);
+
+ return 0;
+}
+
+static int crystalcove_panel_remove(struct platform_device *pdev)
+{
+ struct crystalcove_panel *panel = platform_get_drvdata(pdev);
+
+ DRM_DEBUG_KMS("\n");
+
+ drm_panel_detach(&panel->base);
+ drm_panel_remove(&panel->base);
+
+ crystalcove_panel_disable(&panel->base);
+
+ return 0;
+}
+
+static struct platform_driver crystalcove_panel_driver = {
+ .probe = crystalcove_panel_probe,
+ .remove = crystalcove_panel_remove,
+ .driver = {
+ .name = "crystal_cove_panel",
+ },
+};
+
+module_platform_driver(crystalcove_panel_driver);
+
+MODULE_AUTHOR("Shobhit Kumar <shobhit.kumar@linux.intel.com");
+MODULE_DESCRIPTION("Intel Crystal Cove Panel Driver");
+MODULE_LICENSE("GPL and additional rights");