From 73fe26a48659abd2b85d2f87d3cf2400ddb313d7 Mon Sep 17 00:00:00 2001 From: Stefan Agner Date: Wed, 16 Nov 2016 17:23:27 -0800 Subject: [PATCH] drm/fsl-dcu: introduce kernel parameter to specify fbdev depth Add a kernel parameter legancyfb_depth (like the i.MX drm driver) to control the legancy fbdev depth. Default to the so far hard coded depth of 24-bit. Currently changing the framebuffer depth is not possible from user space when using the fbdev emulation layer... This provides a rudimentary mechanism to change depth without having to change kernel code. Signed-off-by: Stefan Agner --- drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c index 736451616ce4..58ccacaf5a4e 100644 --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_drv.c @@ -32,6 +32,9 @@ #include "fsl_dcu_drm_drv.h" #include "fsl_tcon.h" +static int legacyfb_depth = 24; +module_param(legacyfb_depth, int, 0444); + static bool fsl_dcu_drm_is_volatile_reg(struct device *dev, unsigned int reg) { if (reg == DCU_INT_STATUS || reg == DCU_UPDATE_MODE) @@ -87,7 +90,18 @@ static int fsl_dcu_load(struct drm_device *dev, unsigned long flags) goto done; dev->irq_enabled = true; - fsl_dev->fbdev = drm_fbdev_cma_init(dev, 24, 1, 1); + if (legacyfb_depth != 16 && legacyfb_depth != 24 && + legacyfb_depth != 32) { + dev_warn(dev->dev, + "Invalid legacyfb_depth. Defaulting to 24bpp\n"); + legacyfb_depth = 24; + } + fsl_dev->fbdev = drm_fbdev_cma_init(dev, legacyfb_depth, 1, 1); + if (IS_ERR(fsl_dev->fbdev)) { + ret = PTR_ERR(fsl_dev->fbdev); + fsl_dev->fbdev = NULL; + goto done; + } return 0; done: -- 2.20.1