Re: [PATCH 2/2] drm/panel: add BOE tv101wum-ll2 panel driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 23/07/2024 21:17, Doug Anderson wrote:
Hi,

On Tue, Jul 9, 2024 at 6:06 AM Neil Armstrong <neil.armstrong@xxxxxxxxxx> wrote:

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 5581387707c6..79c90894b6a4 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_DRM_PANEL_BOE_BF060Y8M_AJ0) += panel-boe-bf060y8m-aj0.o
  obj-$(CONFIG_DRM_PANEL_BOE_HIMAX8279D) += panel-boe-himax8279d.o
  obj-$(CONFIG_DRM_PANEL_BOE_TH101MB31UIG002_28A) += panel-boe-th101mb31ig002-28a.o
  obj-$(CONFIG_DRM_PANEL_BOE_TV101WUM_NL6) += panel-boe-tv101wum-nl6.o
+obj-$(CONFIG_DRM_PANEL_BOE_TV101WUM_LL2) += panel-boe-tv101wum-ll2.o

nit: please sort. L comes before N.

Good catch, thx



  obj-$(CONFIG_DRM_PANEL_DSI_CM) += panel-dsi-cm.o
  obj-$(CONFIG_DRM_PANEL_LVDS) += panel-lvds.o
  obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-ll2.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-ll2.c
new file mode 100644
index 000000000000..5513cb48d949
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-ll2.c
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Generated with linux-mdss-dsi-panel-driver-generator from vendor device tree:
+//   Copyright (c) 2013, The Linux Foundation. All rights reserved.
+//   Copyright (c) 2024, Neil Armstrong <neil.armstrong@xxxxxxxxxx>
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/regulator/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>

nit: sort header files?

Will do while I'm it, but I don't personally care of the include order..


+static int boe_tv101wum_ll2_prepare(struct drm_panel *panel)
+{
+       struct boe_tv101wum_ll2 *ctx = to_boe_tv101wum_ll2(panel);
+       struct device *dev = &ctx->dsi->dev;
+       int ret;
+
+       ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies),
+                                   ctx->supplies);
+       if (ret < 0)
+               return ret;
+
+       boe_tv101wum_ll2_reset(ctx);
+
+       ret = boe_tv101wum_ll2_on(ctx);
+       if (ret < 0) {
+               dev_err(dev, "Failed to initialize panel: %d\n", ret);

nit: Do you really need this error message? The "_multi" variants are
all chatty and print the error message, so we don't really need this
here...

Yeah you're right, it's a leftover of the linux-mdss-dsi-panel-driver-generator



+               gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+               return ret;

Shouldn't you turn off the regulators?

Indeed



+static int boe_tv101wum_ll2_unprepare(struct drm_panel *panel)
+{
+       struct boe_tv101wum_ll2 *ctx = to_boe_tv101wum_ll2(panel);
+       struct device *dev = &ctx->dsi->dev;
+       int ret;
+
+       ret = boe_tv101wum_ll2_off(ctx);
+       if (ret < 0)
+               dev_err(dev, "Failed to un-initialize panel: %d\n", ret);

nit: Do you really need this error message? The "_multi" variants are
all chatty and print the error message, so we don't really need this
here...

Another leftover



+
+       gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+
+       regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
+
+       return 0;

Maybe add a comment justifying why you don't return the error code
that boe_tv101wum_ll2_off() returned?

Good point, as far as I remember I always avoided returning errors
when disabling things, I'll investigate



+static int boe_tv101wum_ll2_get_modes(struct drm_panel *panel,
+                                     struct drm_connector *connector)
+{
+       return drm_connector_helper_get_modes_fixed(connector, &boe_tv101wum_ll2_mode);

Random question for you: on panels that don't use the
drm_connector_helper the "bpc" gets set here. Is there a reason why
some panel drivers (like this one) don't set bpc?

Good question, I'll check



+static int boe_tv101wum_ll2_probe(struct mipi_dsi_device *dsi)
+{
+       struct device *dev = &dsi->dev;
+       struct boe_tv101wum_ll2 *ctx;
+       int ret;
+
+       ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+       if (!ctx)
+               return -ENOMEM;
+
+       ctx->supplies[0].supply = "vsp";
+       ctx->supplies[1].supply = "vsn";
+
+       ret = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(ctx->supplies),
+                                     ctx->supplies);

Any chance I can convince you to use devm_regulator_bulk_get_const()?
Then you can list your supply structures as "static const" instead of
having to initialize them via code.

You convinced me!



+       if (ret < 0)
+               return ret;
+
+       ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+       if (IS_ERR(ctx->reset_gpio))
+               return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
+                                    "Failed to get reset-gpios\n");
+
+       ctx->dsi = dsi;
+       mipi_dsi_set_drvdata(dsi, ctx);
+
+       dsi->lanes = 4;
+       dsi->format = MIPI_DSI_FMT_RGB888;
+       dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
+                         MIPI_DSI_MODE_VIDEO_HSE;
+
+       drm_panel_init(&ctx->panel, dev, &boe_tv101wum_ll2_panel_funcs,
+                      DRM_MODE_CONNECTOR_DSI);
+       ctx->panel.prepare_prev_first = true;
+
+       ret = drm_panel_of_backlight(&ctx->panel);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to get backlight\n");
+
+       drm_panel_add(&ctx->panel);

Any chance you could add devm_drm_panel_add() and then use it? Then
you can fully get rid of your remove and error handling since
devm_mipi_dsi_attach() already exists. Note that this would not change
object lifetimes at all since you're already calling
drm_panel_remove() in your remove code--it would just clean up the
code...

Yep I'll use it



+static struct mipi_dsi_driver boe_tv101wum_ll2_driver = {
+       .probe = boe_tv101wum_ll2_probe,
+       .remove = boe_tv101wum_ll2_remove,
+       .driver = {
+               .name = "panel-boe-tv101wum_ll2",
+               .of_match_table = boe_tv101wum_ll2_of_match,
+       },
+};
+module_mipi_dsi_driver(boe_tv101wum_ll2_driver);
+
+MODULE_DESCRIPTION("DRM driver for Boe TV101WUM-LL2 Panel");

Should "Boe" be "BOE" ?

Good point aswell!

Thanks for the review

Neil






[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux