diff options
Diffstat (limited to 'drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c')
| -rw-r--r-- | drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c | 225 | 
1 files changed, 225 insertions, 0 deletions
| diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c new file mode 100644 index 000000000000..136d30484d02 --- /dev/null +++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c @@ -0,0 +1,225 @@ +/* + * Copyright (C) 2014 Texas Instruments + * Author: Tomi Valkeinen <tomi.valkeinen@ti.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program.  If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * As omapdss panel drivers are omapdss specific, but we want to define the + * DT-data in generic manner, we convert the compatible strings of the panel and + * encoder nodes from "panel-foo" to "omapdss,panel-foo". This way we can have + * both correct DT data and omapdss specific drivers. + * + * When we get generic panel drivers to the kernel, this file will be removed. + */ + +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/of_graph.h> +#include <linux/slab.h> +#include <linux/list.h> + +static struct list_head dss_conv_list __initdata; + +static const char prefix[] __initconst = "omapdss,"; + +struct dss_conv_node { +	struct list_head list; +	struct device_node *node; +	bool root; +}; + +static int __init omapdss_count_strings(const struct property *prop) +{ +	const char *p = prop->value; +	int l = 0, total = 0; +	int i; + +	for (i = 0; total < prop->length; total += l, p += l, i++) +		l = strlen(p) + 1; + +	return i; +} + +static void __init omapdss_update_prop(struct device_node *node, char *compat, +	int len) +{ +	struct property *prop; + +	prop = kzalloc(sizeof(*prop), GFP_KERNEL); +	if (!prop) +		return; + +	prop->name = "compatible"; +	prop->value = compat; +	prop->length = len; + +	of_update_property(node, prop); +} + +static void __init omapdss_prefix_strcpy(char *dst, int dst_len, +	const char *src, int src_len) +{ +	size_t total = 0; + +	while (total < src_len) { +		size_t l = strlen(src) + 1; + +		strcpy(dst, prefix); +		dst += strlen(prefix); + +		strcpy(dst, src); +		dst += l; + +		src += l; +		total += l; +	} +} + +/* prepend compatible property strings with "omapdss," */ +static void __init omapdss_omapify_node(struct device_node *node) +{ +	struct property *prop; +	char *new_compat; +	int num_strs; +	int new_len; + +	prop = of_find_property(node, "compatible", NULL); + +	if (!prop || !prop->value) +		return; + +	if (strnlen(prop->value, prop->length) >= prop->length) +		return; + +	/* is it already prefixed? */ +	if (strncmp(prefix, prop->value, strlen(prefix)) == 0) +		return; + +	num_strs = omapdss_count_strings(prop); + +	new_len = prop->length + strlen(prefix) * num_strs; +	new_compat = kmalloc(new_len, GFP_KERNEL); + +	omapdss_prefix_strcpy(new_compat, new_len, prop->value, prop->length); + +	omapdss_update_prop(node, new_compat, new_len); +} + +static void __init omapdss_add_to_list(struct device_node *node, bool root) +{ +	struct dss_conv_node *n = kmalloc(sizeof(struct dss_conv_node), +		GFP_KERNEL); +	if (n) { +		n->node = node; +		n->root = root; +		list_add(&n->list, &dss_conv_list); +	} +} + +static bool __init omapdss_list_contains(const struct device_node *node) +{ +	struct dss_conv_node *n; + +	list_for_each_entry(n, &dss_conv_list, list) { +		if (n->node == node) +			return true; +	} + +	return false; +} + +static void __init omapdss_walk_device(struct device_node *node, bool root) +{ +	struct device_node *n; + +	omapdss_add_to_list(node, root); + +	/* +	 * of_graph_get_remote_port_parent() prints an error if there is no +	 * port/ports node. To avoid that, check first that there's the node. +	 */ +	n = of_get_child_by_name(node, "ports"); +	if (!n) +		n = of_get_child_by_name(node, "port"); +	if (!n) +		return; + +	of_node_put(n); + +	n = NULL; +	while ((n = of_graph_get_next_endpoint(node, n)) != NULL) { +		struct device_node *pn; + +		pn = of_graph_get_remote_port_parent(n); + +		if (!pn) +			continue; + +		if (!of_device_is_available(pn) || omapdss_list_contains(pn)) { +			of_node_put(pn); +			continue; +		} + +		omapdss_walk_device(pn, false); +	} +} + +static const struct of_device_id omapdss_of_match[] __initconst = { +	{ .compatible = "ti,omap2-dss", }, +	{ .compatible = "ti,omap3-dss", }, +	{ .compatible = "ti,omap4-dss", }, +	{ .compatible = "ti,omap5-dss", }, +	{ .compatible = "ti,dra7-dss", }, +	{}, +}; + +static int __init omapdss_boot_init(void) +{ +	struct device_node *dss, *child; + +	INIT_LIST_HEAD(&dss_conv_list); + +	dss = of_find_matching_node(NULL, omapdss_of_match); + +	if (dss == NULL || !of_device_is_available(dss)) +		return 0; + +	omapdss_walk_device(dss, true); + +	for_each_available_child_of_node(dss, child) { +		if (!of_find_property(child, "compatible", NULL)) +			continue; + +		omapdss_walk_device(child, true); +	} + +	while (!list_empty(&dss_conv_list)) { +		struct dss_conv_node *n; + +		n = list_first_entry(&dss_conv_list, struct dss_conv_node, +			list); + +		if (!n->root) +			omapdss_omapify_node(n->node); + +		list_del(&n->list); +		of_node_put(n->node); +		kfree(n); +	} + +	return 0; +} + +subsys_initcall(omapdss_boot_init); | 
