sisfb: add subroutine for detecting XGI Z9

Z7 and Z9 have the same PCI ID, so additional checking is needed to
detect Z9. The method was "documented" in XGI's xgifb driver.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: Thomas Winischhofer <thomas@winischhofer.net>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 20 insertions, 0 deletions

diff --git a/drivers/video/sis/sis.h b/drivers/video/sis/sis.h
index eac7a01925f3..1987f1b7212f 100644
--- a/drivers/video/sis/sis.h
+++ b/drivers/video/sis/sis.h
@@ -495,6 +495,7 @@ struct sis_video_info {
         unsigned int    refresh_rate;
 
         unsigned int    chip;
+        unsigned int    chip_real_id;
         u8              revision_id;
         int             sisvga_enabled;         /* PCI device was enabled */
 
diff --git a/drivers/video/sis/sis_main.c b/drivers/video/sis/sis_main.c
index 364559b12fc5..f0c48e84bcdb 100644
--- a/drivers/video/sis/sis_main.c
+++ b/drivers/video/sis/sis_main.c
@@ -4563,6 +4563,11 @@ sisfb_post_sis315330(struct pci_dev *pdev)
 }
 #endif
 
+static inline int sisfb_xgi_is21(struct sis_video_info *ivideo)
+{
+        return ivideo->chip_real_id == XGI_21;
+}
+
 static void __devinit
 sisfb_post_xgi_delay(struct sis_video_info *ivideo, int delay)
 {
@@ -5802,6 +5807,7 @@ sisfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 #endif
 
         ivideo->chip = chipinfo->chip;
+        ivideo->chip_real_id = chipinfo->chip;
         ivideo->sisvga_engine = chipinfo->vgaengine;
         ivideo->hwcursor_size = chipinfo->hwcursor_size;
         ivideo->CRT2_write_enable = chipinfo->CRT2_write_enable;
@@ -6035,6 +6041,18 @@ sisfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
                 sisfb_detect_custom_timing(ivideo);
         }
 
+#ifdef CONFIG_FB_SIS_315
+        if (ivideo->chip == XGI_20) {
+                /* Check if our Z7 chip is actually Z9 */
+                SiS_SetRegOR(SISCR, 0x4a, 0x40);        /* GPIOG EN */
+                reg = SiS_GetReg(SISCR, 0x48);
+                if (reg & 0x02) {                       /* GPIOG */
+                        ivideo->chip_real_id = XGI_21;
+                        dev_info(&pdev->dev, "Z9 detected\n");
+                }
+        }
+#endif
+
         /* POST card in case this has not been done by the BIOS */
         if( (!ivideo->sisvga_enabled)
 #if !defined(__i386__) && !defined(__x86_64__)
diff --git a/drivers/video/sis/vgatypes.h b/drivers/video/sis/vgatypes.h
index 12c0dfaf2518..e3f9976cfef0 100644
--- a/drivers/video/sis/vgatypes.h
+++ b/drivers/video/sis/vgatypes.h
@@ -87,6 +87,7 @@ typedef enum _SIS_CHIP_TYPE {
     SIS_341,
     SIS_342,
     XGI_20  = 75,
+    XGI_21,
     XGI_40,
     MAX_SIS_CHIP
 } SIS_CHIP_TYPE;