From 9e2d410d18bf93c620877a4ea0cab213362a2dda Mon Sep 17 00:00:00 2001 From: Russell King Date: Sun, 3 Nov 2013 14:04:47 +0000 Subject: imx-drm: imx-drm-core: provide helper function to parse possible crtcs Provide a helper function to parse possible crtcs before the encoder is registered. The crtc mask is derived from the position of the CRTCs registered in the drm_device. Acked-by: Philipp Zabel Acked-by: Shawn Guo Reviewed-by: Fabio Estevam Signed-off-by: Russell King --- drivers/staging/imx-drm/imx-drm-core.c | 66 ++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) (limited to 'drivers/staging/imx-drm/imx-drm-core.c') diff --git a/drivers/staging/imx-drm/imx-drm-core.c b/drivers/staging/imx-drm/imx-drm-core.c index 3d1c6b6c4388..5cac6ee24472 100644 --- a/drivers/staging/imx-drm/imx-drm-core.c +++ b/drivers/staging/imx-drm/imx-drm-core.c @@ -658,6 +658,72 @@ err_busy: } EXPORT_SYMBOL_GPL(imx_drm_add_encoder); +/* + * Find the DRM CRTC possible mask for the device node cookie/id. + * + * The encoder possible masks are defined by their position in the + * mode_config crtc_list. This means that CRTCs must not be added + * or removed once the DRM device has been fully initialised. + */ +static uint32_t imx_drm_find_crtc_mask(struct imx_drm_device *imxdrm, + void *cookie, int id) +{ + unsigned i; + + for (i = 0; i < MAX_CRTC; i++) { + struct imx_drm_crtc *imx_drm_crtc = imxdrm->crtc[i]; + if (imx_drm_crtc && imx_drm_crtc->cookie.id == id && + imx_drm_crtc->cookie.cookie == cookie) + return drm_crtc_mask(imx_drm_crtc->crtc); + } + + return 0; +} + +int imx_drm_encoder_parse_of(struct drm_device *drm, + struct drm_encoder *encoder, struct device_node *np) +{ + struct imx_drm_device *imxdrm = drm->dev_private; + uint32_t crtc_mask = 0; + int i, ret = 0; + + for (i = 0; !ret; i++) { + struct of_phandle_args args; + uint32_t mask; + int id; + + ret = of_parse_phandle_with_args(np, "crtcs", "#crtc-cells", i, + &args); + if (ret == -ENOENT) + break; + if (ret < 0) + return ret; + + id = args.args_count > 0 ? args.args[0] : 0; + mask = imx_drm_find_crtc_mask(imxdrm, args.np, id); + of_node_put(args.np); + + /* + * If we failed to find the CRTC(s) which this encoder is + * supposed to be connected to, it's because the CRTC has + * not been registered yet. Defer probing, and hope that + * the required CRTC is added later. + */ + if (mask == 0) + return -EPROBE_DEFER; + + crtc_mask |= mask; + } + + encoder->possible_crtcs = crtc_mask; + + /* FIXME: this is the mask of outputs which can clone this output. */ + encoder->possible_clones = ~0; + + return 0; +} +EXPORT_SYMBOL_GPL(imx_drm_encoder_parse_of); + int imx_drm_encoder_add_possible_crtcs( struct imx_drm_encoder *imx_drm_encoder, struct device_node *np) -- cgit v1.2.3