aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/video/omap2
diff options
context:
space:
mode:
authorTomi Valkeinen <tomi.valkeinen@ti.com>2012-01-17 11:09:57 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-03-12 12:31:38 -0700
commit338b2875624561c3ea57d95519497527c06d123f (patch)
tree5de678e9f536d6b1cfcc62d43d553ce48fbb6370 /drivers/video/omap2
parent27b7be99f3d5cca4eeb179a2cb4bf435e356665c (diff)
downloadkernel_samsung_smdk4412-338b2875624561c3ea57d95519497527c06d123f.zip
kernel_samsung_smdk4412-338b2875624561c3ea57d95519497527c06d123f.tar.gz
kernel_samsung_smdk4412-338b2875624561c3ea57d95519497527c06d123f.tar.bz2
OMAPDSS: HDMI: PHY burnout fix
commit c49d005b6cc8491fad5b24f82805be2d6bcbd3dd upstream. A hardware bug in the OMAP4 HDMI PHY causes physical damage to the board if the HDMI PHY is kept powered on when the cable is not connected. This patch solves the problem by adding hot-plug-detection into the HDMI IP driver. This is not a real HPD support in the sense that nobody else than the IP driver gets to know about the HPD events, but is only meant to fix the HW bug. The strategy is simple: If the display device is turned off by the user, the PHY power is set to OFF. When the display device is turned on by the user, the PHY power is set either to LDOON or TXON, depending on whether the HDMI cable is connected. The reason to avoid PHY OFF when the display device is on, but the cable is disconnected, is that when the PHY is turned OFF, the HDMI IP is not "ticking" and thus the DISPC does not receive pixel clock from the HDMI IP. This would, for example, prevent any VSYNCs from happening, and would thus affect the users of omapdss. By using LDOON when the cable is disconnected we'll avoid the HW bug, but keep the HDMI working as usual from the user's point of view. Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/video/omap2')
-rw-r--r--drivers/video/omap2/dss/hdmi.c3
-rw-r--r--drivers/video/omap2/dss/ti_hdmi.h4
-rw-r--r--drivers/video/omap2/dss/ti_hdmi_4xxx_ip.c68
3 files changed, 71 insertions, 4 deletions
diff --git a/drivers/video/omap2/dss/hdmi.c b/drivers/video/omap2/dss/hdmi.c
index c56378c..7099c31 100644
--- a/drivers/video/omap2/dss/hdmi.c
+++ b/drivers/video/omap2/dss/hdmi.c
@@ -490,6 +490,7 @@ bool omapdss_hdmi_detect(void)
int omapdss_hdmi_display_enable(struct omap_dss_device *dssdev)
{
+ struct omap_dss_hdmi_data *priv = dssdev->data;
int r = 0;
DSSDBG("ENTER hdmi_display_enable\n");
@@ -502,6 +503,8 @@ int omapdss_hdmi_display_enable(struct omap_dss_device *dssdev)
goto err0;
}
+ hdmi.ip_data.hpd_gpio = priv->hpd_gpio;
+
r = omap_dss_start_device(dssdev);
if (r) {
DSSERR("failed to start device\n");
diff --git a/drivers/video/omap2/dss/ti_hdmi.h b/drivers/video/omap2/dss/ti_hdmi.h
index 2c3443d..ec337b5d 100644
--- a/drivers/video/omap2/dss/ti_hdmi.h
+++ b/drivers/video/omap2/dss/ti_hdmi.h
@@ -121,6 +121,10 @@ struct hdmi_ip_data {
const struct ti_hdmi_ip_ops *ops;
struct hdmi_config cfg;
struct hdmi_pll_info pll_data;
+
+ /* ti_hdmi_4xxx_ip private data. These should be in a separate struct */
+ int hpd_gpio;
+ bool phy_tx_enabled;
};
int ti_hdmi_4xxx_phy_enable(struct hdmi_ip_data *ip_data);
void ti_hdmi_4xxx_phy_disable(struct hdmi_ip_data *ip_data);
diff --git a/drivers/video/omap2/dss/ti_hdmi_4xxx_ip.c b/drivers/video/omap2/dss/ti_hdmi_4xxx_ip.c
index e1a6ce5..3683404 100644
--- a/drivers/video/omap2/dss/ti_hdmi_4xxx_ip.c
+++ b/drivers/video/omap2/dss/ti_hdmi_4xxx_ip.c
@@ -28,6 +28,7 @@
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/seq_file.h>
+#include <linux/gpio.h>
#include "ti_hdmi_4xxx_ip.h"
#include "dss.h"
@@ -223,6 +224,49 @@ void ti_hdmi_4xxx_pll_disable(struct hdmi_ip_data *ip_data)
hdmi_set_pll_pwr(ip_data, HDMI_PLLPWRCMD_ALLOFF);
}
+static int hdmi_check_hpd_state(struct hdmi_ip_data *ip_data)
+{
+ unsigned long flags;
+ bool hpd;
+ int r;
+ /* this should be in ti_hdmi_4xxx_ip private data */
+ static DEFINE_SPINLOCK(phy_tx_lock);
+
+ spin_lock_irqsave(&phy_tx_lock, flags);
+
+ hpd = gpio_get_value(ip_data->hpd_gpio);
+
+ if (hpd == ip_data->phy_tx_enabled) {
+ spin_unlock_irqrestore(&phy_tx_lock, flags);
+ return 0;
+ }
+
+ if (hpd)
+ r = hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_TXON);
+ else
+ r = hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_LDOON);
+
+ if (r) {
+ DSSERR("Failed to %s PHY TX power\n",
+ hpd ? "enable" : "disable");
+ goto err;
+ }
+
+ ip_data->phy_tx_enabled = hpd;
+err:
+ spin_unlock_irqrestore(&phy_tx_lock, flags);
+ return r;
+}
+
+static irqreturn_t hpd_irq_handler(int irq, void *data)
+{
+ struct hdmi_ip_data *ip_data = data;
+
+ hdmi_check_hpd_state(ip_data);
+
+ return IRQ_HANDLED;
+}
+
int ti_hdmi_4xxx_phy_enable(struct hdmi_ip_data *ip_data)
{
u16 r = 0;
@@ -232,10 +276,6 @@ int ti_hdmi_4xxx_phy_enable(struct hdmi_ip_data *ip_data)
if (r)
return r;
- r = hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_TXON);
- if (r)
- return r;
-
/*
* Read address 0 in order to get the SCP reset done completed
* Dummy access performed to make sure reset is done
@@ -257,12 +297,32 @@ int ti_hdmi_4xxx_phy_enable(struct hdmi_ip_data *ip_data)
/* Write to phy address 3 to change the polarity control */
REG_FLD_MOD(phy_base, HDMI_TXPHY_PAD_CFG_CTRL, 0x1, 27, 27);
+ r = request_threaded_irq(gpio_to_irq(ip_data->hpd_gpio),
+ NULL, hpd_irq_handler,
+ IRQF_DISABLED | IRQF_TRIGGER_RISING |
+ IRQF_TRIGGER_FALLING, "hpd", ip_data);
+ if (r) {
+ DSSERR("HPD IRQ request failed\n");
+ hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_OFF);
+ return r;
+ }
+
+ r = hdmi_check_hpd_state(ip_data);
+ if (r) {
+ free_irq(gpio_to_irq(ip_data->hpd_gpio), ip_data);
+ hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_OFF);
+ return r;
+ }
+
return 0;
}
void ti_hdmi_4xxx_phy_disable(struct hdmi_ip_data *ip_data)
{
+ free_irq(gpio_to_irq(ip_data->hpd_gpio), ip_data);
+
hdmi_set_phy_pwr(ip_data, HDMI_PHYPWRCMD_OFF);
+ ip_data->phy_tx_enabled = false;
}
static int hdmi_core_ddc_init(struct hdmi_ip_data *ip_data)