viafb: add interface for output device configuration

This patch extends the proc entry to contain a possibility to view and
change the output devices for each IGA. This is useful for debugging
output problems as it provides a reliable way to query which low level
devices are active after VIAs output device configuration nightmare
happended. It's as well suitable for daily use as one can change the
output configuration on the fly for example to connect a projector.
At the moment it's still unstable. The reason is that we have to handle
a bunch of undocumented output devices (those without a proper name) and
that this patch is the first step to collect and verify the needed
information. Basically the only configuration change that is expected to
work at the moment is switching output devices between IGA1 and IGA2.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Cc: Joseph Chan <JosephChan@via.com.tw>
Cc: Andrew Morton <akpm@linux-foundation.org>

drivers/video/via/hw.c

@@ -718,6 +718,16 @@ static struct rgbLUT palLUT_table[] = {
 								     0x00}
 };
 
+static struct via_device_mapping device_mapping[] = {
+	{VIA_6C, "6C"},
+	{VIA_93, "93"},
+	{VIA_96, "96"},
+	{VIA_CRT, "CRT"},
+	{VIA_DVP1, "DVP1"},
+	{VIA_LVDS1, "LVDS1"},
+	{VIA_LVDS2, "LVDS2"}
+};
+
 static void load_fix_bit_crtc_reg(void);
 static void __devinit init_gfx_chip_info(int chip_type);
 static void __devinit init_tmds_chip_info(void);
@@ -1026,6 +1036,49 @@ void via_set_source(u32 devices, u8 iga)
 		set_lvds2_source(iga);
 }
 
+u32 via_parse_odev(char *input, char **end)
+{
+	char *ptr = input;
+	u32 odev = 0;
+	bool next = true;
+	int i, len;
+
+	while (next) {
+		next = false;
+		for (i = 0; i < ARRAY_SIZE(device_mapping); i++) {
+			len = strlen(device_mapping[i].name);
+			if (!strncmp(ptr, device_mapping[i].name, len)) {
+				odev |= device_mapping[i].device;
+				ptr += len;
+				if (*ptr == ',') {
+					ptr++;
+					next = true;
+				}
+			}
+		}
+	}
+
+	*end = ptr;
+	return odev;
+}
+
+void via_odev_to_seq(struct seq_file *m, u32 odev)
+{
+	int i, count = 0;
+
+	for (i = 0; i < ARRAY_SIZE(device_mapping); i++) {
+		if (odev & device_mapping[i].device) {
+			if (count > 0)
+				seq_putc(m, ',');
+
+			seq_puts(m, device_mapping[i].name);
+			count++;
+		}
+	}
+
+	seq_putc(m, '\n');
+}
+
 static void load_fix_bit_crtc_reg(void)
 {
 	/* always set to 1 */

drivers/video/via/hw.h

@@ -22,6 +22,8 @@
 #ifndef __HW_H__
 #define __HW_H__
 
+#include <linux/seq_file.h>
+
 #include "viamode.h"
 #include "global.h"
 #include "via_modesetting.h"
@@ -882,6 +884,11 @@ struct pci_device_id_info {
 	u32 chip_index;
 };
 
+struct via_device_mapping {
+	u32 device;
+	const char *name;
+};
+
 extern unsigned int viafb_second_virtual_xres;
 extern int viafb_SAMM_ON;
 extern int viafb_dual_fb;
@@ -899,6 +906,9 @@ void viafb_load_reg(int timing_value, int viafb_load_reg_num,
 	      int io_type);
 void viafb_crt_disable(void);
 void viafb_crt_enable(void);
+void via_set_source(u32 devices, u8 iga);
+u32 via_parse_odev(char *input, char **end);
+void via_odev_to_seq(struct seq_file *m, u32 odev);
 void init_ad9389(void);
 /* Access I/O Function */
 void viafb_lock_crt(void);

drivers/video/via/viafbdev.c

@@ -1431,38 +1431,169 @@ static const struct file_operations viafb_vt1636_proc_fops = {
 	.write		= viafb_vt1636_proc_write,
 };
 
-static void viafb_init_proc(struct proc_dir_entry **viafb_entry)
-{
-	*viafb_entry = proc_mkdir("viafb", NULL);
-	if (*viafb_entry) {
-		proc_create("dvp0", 0, *viafb_entry, &viafb_dvp0_proc_fops);
-		proc_create("dvp1", 0, *viafb_entry, &viafb_dvp1_proc_fops);
-		proc_create("dfph", 0, *viafb_entry, &viafb_dfph_proc_fops);
-		proc_create("dfpl", 0, *viafb_entry, &viafb_dfpl_proc_fops);
-		if (VT1636_LVDS == viaparinfo->chip_info->lvds_chip_info.
-			lvds_chip_name || VT1636_LVDS ==
-		    viaparinfo->chip_info->lvds_chip_info2.lvds_chip_name) {
-			proc_create("vt1636", 0, *viafb_entry, &viafb_vt1636_proc_fops);
-		}
+#endif /* CONFIG_FB_VIA_DIRECT_PROCFS */
 
+static ssize_t odev_update(const char __user *buffer, size_t count, u32 *odev)
+{
+	char buf[64], *ptr = buf;
+	u32 devices;
+	bool add, sub;
+
+	if (count < 1 || count > 63)
+		return -EINVAL;
+	if (copy_from_user(&buf[0], buffer, count))
+		return -EFAULT;
+	buf[count] = '\0';
+	add = buf[0] == '+';
+	sub = buf[0] == '-';
+	if (add || sub)
+		ptr++;
+	devices = via_parse_odev(ptr, &ptr);
+	if (*ptr == '\n')
+		ptr++;
+	if (*ptr != 0)
+		return -EINVAL;
+	if (add)
+		*odev |= devices;
+	else if (sub)
+		*odev &= ~devices;
+	else
+		*odev = devices;
+	return count;
+}
+
+static int viafb_iga1_odev_proc_show(struct seq_file *m, void *v)
+{
+	via_odev_to_seq(m, viaparinfo->shared->iga1_devices);
+	return 0;
+}
+
+static int viafb_iga1_odev_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, viafb_iga1_odev_proc_show, NULL);
+}
+
+static ssize_t viafb_iga1_odev_proc_write(struct file *file,
+	const char __user *buffer, size_t count, loff_t *pos)
+{
+	u32 dev_on, dev_off, dev_old, dev_new;
+	ssize_t res;
+
+	dev_old = dev_new = viaparinfo->shared->iga1_devices;
+	res = odev_update(buffer, count, &dev_new);
+	if (res != count)
+		return res;
+	dev_off = dev_old & ~dev_new;
+	dev_on = dev_new & ~dev_old;
+	viaparinfo->shared->iga1_devices = dev_new;
+	viaparinfo->shared->iga2_devices &= ~dev_new;
+	via_set_source(dev_new, IGA1);
+	return res;
+}
+
+static const struct file_operations viafb_iga1_odev_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= viafb_iga1_odev_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.write		= viafb_iga1_odev_proc_write,
+};
+
+static int viafb_iga2_odev_proc_show(struct seq_file *m, void *v)
+{
+	via_odev_to_seq(m, viaparinfo->shared->iga2_devices);
+	return 0;
+}
+
+static int viafb_iga2_odev_proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, viafb_iga2_odev_proc_show, NULL);
+}
+
+static ssize_t viafb_iga2_odev_proc_write(struct file *file,
+	const char __user *buffer, size_t count, loff_t *pos)
+{
+	u32 dev_on, dev_off, dev_old, dev_new;
+	ssize_t res;
+
+	dev_old = dev_new = viaparinfo->shared->iga2_devices;
+	res = odev_update(buffer, count, &dev_new);
+	if (res != count)
+		return res;
+	dev_off = dev_old & ~dev_new;
+	dev_on = dev_new & ~dev_old;
+	viaparinfo->shared->iga2_devices = dev_new;
+	viaparinfo->shared->iga1_devices &= ~dev_new;
+	via_set_source(dev_new, IGA2);
+	return res;
+}
+
+static const struct file_operations viafb_iga2_odev_proc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= viafb_iga2_odev_proc_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+	.write		= viafb_iga2_odev_proc_write,
+};
+
+#define IS_VT1636(lvds_chip)	((lvds_chip).lvds_chip_name == VT1636_LVDS)
+static void viafb_init_proc(struct viafb_shared *shared)
+{
+	struct proc_dir_entry *iga1_entry, *iga2_entry,
+		*viafb_entry = proc_mkdir("viafb", NULL);
+
+	shared->proc_entry = viafb_entry;
+	if (viafb_entry) {
+#ifdef CONFIG_FB_VIA_DIRECT_PROCFS
+		proc_create("dvp0", 0, viafb_entry, &viafb_dvp0_proc_fops);
+		proc_create("dvp1", 0, viafb_entry, &viafb_dvp1_proc_fops);
+		proc_create("dfph", 0, viafb_entry, &viafb_dfph_proc_fops);
+		proc_create("dfpl", 0, viafb_entry, &viafb_dfpl_proc_fops);
+		if (IS_VT1636(shared->chip_info.lvds_chip_info)
+			|| IS_VT1636(shared->chip_info.lvds_chip_info2))
+			proc_create("vt1636", 0, viafb_entry,
+				&viafb_vt1636_proc_fops);
+#endif /* CONFIG_FB_VIA_DIRECT_PROCFS */
+
+		iga1_entry = proc_mkdir("iga1", viafb_entry);
+		shared->iga1_proc_entry = iga1_entry;
+		proc_create("output_devices", 0, iga1_entry,
+			&viafb_iga1_odev_proc_fops);
+		iga2_entry = proc_mkdir("iga2", viafb_entry);
+		shared->iga2_proc_entry = iga2_entry;
+		proc_create("output_devices", 0, iga2_entry,
+			&viafb_iga2_odev_proc_fops);
 	}
 }
-static void viafb_remove_proc(struct proc_dir_entry *viafb_entry)
+static void viafb_remove_proc(struct viafb_shared *shared)
 {
-	struct chip_information *chip_info = &viaparinfo->shared->chip_info;
+	struct proc_dir_entry *viafb_entry = shared->proc_entry,
+		*iga1_entry = shared->iga1_proc_entry,
+		*iga2_entry = shared->iga2_proc_entry;
 
+	if (!viafb_entry)
+		return;
+
+	remove_proc_entry("output_devices", iga2_entry);
+	remove_proc_entry("iga2", viafb_entry);
+	remove_proc_entry("output_devices", iga1_entry);
+	remove_proc_entry("iga1", viafb_entry);
+
+#ifdef CONFIG_FB_VIA_DIRECT_PROCFS
 	remove_proc_entry("dvp0", viafb_entry);/* parent dir */
 	remove_proc_entry("dvp1", viafb_entry);
 	remove_proc_entry("dfph", viafb_entry);
 	remove_proc_entry("dfpl", viafb_entry);
-	if (chip_info->lvds_chip_info.lvds_chip_name == VT1636_LVDS
-		|| chip_info->lvds_chip_info2.lvds_chip_name == VT1636_LVDS)
+	if (IS_VT1636(shared->chip_info.lvds_chip_info)
+		|| IS_VT1636(shared->chip_info.lvds_chip_info2))
 		remove_proc_entry("vt1636", viafb_entry);
+#endif /* CONFIG_FB_VIA_DIRECT_PROCFS */
 
 	remove_proc_entry("viafb", NULL);
 }
-
-#endif /* CONFIG_FB_VIA_DIRECT_PROCFS */
+#undef IS_VT1636
 
 static int parse_mode(const char *str, u32 *xres, u32 *yres)
 {
@@ -1671,9 +1802,7 @@ int __devinit via_fb_pci_probe(struct viafb_dev *vdev)
 		  viafbinfo->node, viafbinfo->fix.id, default_var.xres,
 		  default_var.yres, default_var.bits_per_pixel);
 
-#ifdef CONFIG_FB_VIA_DIRECT_PROCFS
-	viafb_init_proc(&viaparinfo->shared->proc_entry);
-#endif
+	viafb_init_proc(viaparinfo->shared);
 	viafb_init_dac(IGA2);
 	return 0;
 
@@ -1700,9 +1829,7 @@ void __devexit via_fb_pci_remove(struct pci_dev *pdev)
 	unregister_framebuffer(viafbinfo);
 	if (viafb_dual_fb)
 		unregister_framebuffer(viafbinfo1);
-#ifdef CONFIG_FB_VIA_DIRECT_PROCFS
-	viafb_remove_proc(viaparinfo->shared->proc_entry);
-#endif
+	viafb_remove_proc(viaparinfo->shared);
 	framebuffer_release(viafbinfo);
 	if (viafb_dual_fb)
 		framebuffer_release(viafbinfo1);

drivers/video/via/viafbdev.h

@@ -44,6 +44,8 @@ struct viafb_shared {
 	u32 iga2_devices;
 
 	struct proc_dir_entry *proc_entry;	/*viafb proc entry */
+	struct proc_dir_entry *iga1_proc_entry;
+	struct proc_dir_entry *iga2_proc_entry;
 	struct viafb_dev *vdev;			/* Global dev info */
 
 	/* All the information will be needed to set engine */