From 45bfe97276856b866dd73fdadb65fb928c0c9bc1 Mon Sep 17 00:00:00 2001 From: Andres Salomon Date: Thu, 10 Feb 2011 17:48:38 -0800 Subject: [PATCH] staging: olpc_dcon: move fb stuff info dcon_priv, and clean up fb handling - move fbinfo and ignore_fb_events into dcon_priv - add calls to {un,}lock_fb_info before calling fb_blank - fail to load the driver if there are no registered framebuffers That last one fixes a potential oops, where if the dcon driver loads without a framebuffer registered, fb_blank will end up being passed a NULL (and will attempt to dereference it). Signed-off-by: Andres Salomon Signed-off-by: Greg Kroah-Hartman --- drivers/staging/olpc_dcon/olpc_dcon.c | 60 +++++++++++++++++---------- 1 file changed, 37 insertions(+), 23 deletions(-) diff --git a/drivers/staging/olpc_dcon/olpc_dcon.c b/drivers/staging/olpc_dcon/olpc_dcon.c index 710d88094d48..d3c280052d16 100644 --- a/drivers/staging/olpc_dcon/olpc_dcon.c +++ b/drivers/staging/olpc_dcon/olpc_dcon.c @@ -55,6 +55,7 @@ static struct dcon_platform_data *pdata; struct dcon_priv { struct i2c_client *client; + struct fb_info *fbinfo; struct work_struct switch_source; struct notifier_block reboot_nb; @@ -66,6 +67,8 @@ struct dcon_priv { /* Current output type; true == mono, false == color */ bool mono; bool asleep; + /* This get set while controlling fb blank state from the driver */ + bool ignore_fb_events; }; /* I2C structures */ @@ -78,11 +81,6 @@ static struct platform_device *dcon_device; /* Backlight device */ static struct backlight_device *dcon_bl_dev; -static struct fb_info *fbinfo; - -/* set this to 1 while controlling fb blank state from this driver */ -static int ignore_fb_events = 0; - /* Current source, initialized at probe time */ static int dcon_source; @@ -346,8 +344,32 @@ void dcon_load_holdoff(void) mdelay(4); } } -/* Set the source of the display (CPU or DCON) */ +static bool dcon_blank_fb(struct dcon_priv *dcon, bool blank) +{ + int err; + + if (!lock_fb_info(dcon->fbinfo)) { + dev_err(&dcon->client->dev, "unable to lock framebuffer\n"); + return false; + } + console_lock(); + dcon->ignore_fb_events = true; + err = fb_blank(dcon->fbinfo, + blank ? FB_BLANK_POWERDOWN : FB_BLANK_UNBLANK); + dcon->ignore_fb_events = false; + console_unlock(); + unlock_fb_info(dcon->fbinfo); + + if (err) { + dev_err(&dcon->client->dev, "couldn't %sblank framebuffer\n", + blank ? "" : "un"); + return false; + } + return true; +} + +/* Set the source of the display (CPU or DCON) */ static void dcon_source_switch(struct work_struct *work) { struct dcon_priv *dcon = container_of(work, struct dcon_priv, @@ -391,17 +413,11 @@ static void dcon_source_switch(struct work_struct *work) * * For now, we just hope.. */ - console_lock(); - ignore_fb_events = 1; - if (fb_blank(fbinfo, FB_BLANK_UNBLANK)) { - ignore_fb_events = 0; - console_unlock(); + if (!dcon_blank_fb(dcon, false)) { printk(KERN_ERR "olpc-dcon: Failed to enter CPU mode\n"); dcon_pending = DCON_SOURCE_DCON; return; } - ignore_fb_events = 0; - console_unlock(); /* And turn off the DCON */ pdata->set_dconload(1); @@ -453,13 +469,7 @@ static void dcon_source_switch(struct work_struct *work) } } - console_lock(); - ignore_fb_events = 1; - if (fb_blank(fbinfo, FB_BLANK_POWERDOWN)) - printk(KERN_ERR "olpc-dcon: couldn't blank fb!\n"); - ignore_fb_events = 0; - console_unlock(); - + dcon_blank_fb(dcon, true); printk(KERN_INFO "olpc-dcon: The DCON has control\n"); break; } @@ -678,7 +688,7 @@ static int dcon_fb_notifier(struct notifier_block *self, fbevent_nb); int *blank = (int *) evdata->data; if (((event != FB_EVENT_BLANK) && (event != FB_EVENT_CONBLANK)) || - ignore_fb_events) + dcon->ignore_fb_events) return 0; dcon_sleep(dcon, *blank ? true : false); return 0; @@ -708,8 +718,12 @@ static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id) i2c_set_clientdata(client, dcon); - if (num_registered_fb >= 1) - fbinfo = registered_fb[0]; + if (num_registered_fb < 1) { + dev_err(&client->dev, "DCON driver requires a registered fb\n"); + rc = -EIO; + goto einit; + } + dcon->fbinfo = registered_fb[0]; rc = dcon_hw_init(dcon, 1); if (rc) -- 2.25.1