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drm/bridge/sii8620: use micro-USB cable detection logic to detect MHL

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Currently MHL chip must be turned on permanently to detect MHL cable. It
duplicates micro-USB controller's (MUIC) functionality and consumes
unnecessary power. Lets use extcon attached to MUIC to enable MHL chip
only if it detects MHL cable.

Signed-off-by: Maciej Purski <m.purski@samsung.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Acked-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
This commit is contained in:
Maciej Purski 2018-02-27 08:11:34 +01:00 committed by Chanwoo Choi
parent 370ed7a9b9
commit 6888384421
1 changed files with 94 additions and 3 deletions
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97
drivers/gpu/drm/bridge/sil-sii8620.c
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@ -17,6 +17,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/extcon.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
@ -25,6 +26,7 @@
#include <linux/list.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_graph.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
@ -81,6 +83,10 @@ struct sii8620 {
struct edid *edid;
unsigned int gen2_write_burst:1;
enum sii8620_mt_state mt_state;
struct extcon_dev *extcon;
struct notifier_block extcon_nb;
struct work_struct extcon_wq;
int cable_state;
struct list_head mt_queue;
struct {
int r_size;
@ -2170,6 +2176,77 @@ static void sii8620_init_rcp_input_dev(struct sii8620 *ctx)
ctx->rc_dev = rc_dev;
}
static void sii8620_cable_out(struct sii8620 *ctx)
{
disable_irq(to_i2c_client(ctx->dev)->irq);
sii8620_hw_off(ctx);
}
static void sii8620_extcon_work(struct work_struct *work)
{
struct sii8620 *ctx =
container_of(work, struct sii8620, extcon_wq);
int state = extcon_get_state(ctx->extcon, EXTCON_DISP_MHL);
if (state == ctx->cable_state)
return;
ctx->cable_state = state;
if (state > 0)
sii8620_cable_in(ctx);
else
sii8620_cable_out(ctx);
}
static int sii8620_extcon_notifier(struct notifier_block *self,
unsigned long event, void *ptr)
{
struct sii8620 *ctx =
container_of(self, struct sii8620, extcon_nb);
schedule_work(&ctx->extcon_wq);
return NOTIFY_DONE;
}
static int sii8620_extcon_init(struct sii8620 *ctx)
{
struct extcon_dev *edev;
struct device_node *musb, *muic;
int ret;
/* get micro-USB connector node */
musb = of_graph_get_remote_node(ctx->dev->of_node, 1, -1);
/* next get micro-USB Interface Controller node */
muic = of_get_next_parent(musb);
if (!muic) {
dev_info(ctx->dev, "no extcon found, switching to 'always on' mode\n");
return 0;
}
edev = extcon_find_edev_by_node(muic);
of_node_put(muic);
if (IS_ERR(edev)) {
if (PTR_ERR(edev) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(ctx->dev, "Invalid or missing extcon\n");
return PTR_ERR(edev);
}
ctx->extcon = edev;
ctx->extcon_nb.notifier_call = sii8620_extcon_notifier;
INIT_WORK(&ctx->extcon_wq, sii8620_extcon_work);
ret = extcon_register_notifier(edev, EXTCON_DISP_MHL, &ctx->extcon_nb);
if (ret) {
dev_err(ctx->dev, "failed to register notifier for MHL\n");
return ret;
}
return 0;
}
static inline struct sii8620 *bridge_to_sii8620(struct drm_bridge *bridge)
{
return container_of(bridge, struct sii8620, bridge);
@ -2302,13 +2379,20 @@ static int sii8620_probe(struct i2c_client *client,
if (ret)
return ret;
ret = sii8620_extcon_init(ctx);
if (ret < 0) {
dev_err(ctx->dev, "failed to initialize EXTCON\n");
return ret;
}
i2c_set_clientdata(client, ctx);
ctx->bridge.funcs = &sii8620_bridge_funcs;
ctx->bridge.of_node = dev->of_node;
drm_bridge_add(&ctx->bridge);
sii8620_cable_in(ctx);
if (!ctx->extcon)
sii8620_cable_in(ctx);
return 0;
}
@ -2317,8 +2401,15 @@ static int sii8620_remove(struct i2c_client *client)
{
struct sii8620 *ctx = i2c_get_clientdata(client);
disable_irq(to_i2c_client(ctx->dev)->irq);
sii8620_hw_off(ctx);
if (ctx->extcon) {
extcon_unregister_notifier(ctx->extcon, EXTCON_DISP_MHL,
&ctx->extcon_nb);
flush_work(&ctx->extcon_wq);
if (ctx->cable_state > 0)
sii8620_cable_out(ctx);
} else {
sii8620_cable_out(ctx);
}
drm_bridge_remove(&ctx->bridge);
return 0;