[v4,4/9] i2c: piix4: Move SMBus controller base address detect into function

Commit Message

Bowman, Terry Jan. 30, 2022, 6:41 p.m. UTC

Move SMBus controller base address detection into function. Refactor
is in preparation for following MMIO changes.

Signed-off-by: Terry Bowman <[e-mail]>
---
 drivers/i2c/busses/i2c-piix4.c | 71 +++++++++++++++++++++-------------
 1 file changed, 45 insertions(+), 26 deletions(-)

Comments

Jean Delvare Feb. 8, 2022, 3:09 p.m. UTC | #1

On Sun, 30 Jan 2022 12:41:25 -0600, Terry Bowman wrote:
>  static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
>  			     const struct pci_device_id *id, u8 aux)
>  {
> -	unsigned short piix4_smba;
> -	u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status, port_sel;
> +	u8 smb_en, smb_en_status, port_sel;
>  	u8 i2ccfg, i2ccfg_offset = 0x10;
> +	unsigned short piix4_smba;
>  	int retval;
>  
>  	/* SB800 and later SMBus does not support forcing address */

I suggest not moving variables around unless there's a compelling to do
that. Else you make your patches larger (and slightly harder to
review), plus it increases the risks of context conflicts when
backporting other changes.

Thanks,

Patch

diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 5a98970ac60a..eab06e9e5fdf 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -282,12 +282,52 @@  static int piix4_setup(struct pci_dev *PIIX4_dev,
 	return piix4_smba;
 }
 
+static int piix4_setup_sb800_smba(struct pci_dev *PIIX4_dev,
+				  u8 smb_en,
+				  u8 aux,
+				  u8 *smb_en_status,
+				  unsigned short *piix4_smba)
+{
+	u8 smba_en_lo;
+	u8 smba_en_hi;
+	int retval;
+
+	retval = piix4_sb800_region_request(&PIIX4_dev->dev);
+	if (retval)
+		return retval;
+
+	outb_p(smb_en, SB800_PIIX4_SMB_IDX);
+	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
+	outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
+	smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
+
+	piix4_sb800_region_release(&PIIX4_dev->dev);
+
+	if (!smb_en) {
+		*smb_en_status = smba_en_lo & 0x10;
+		*piix4_smba = smba_en_hi << 8;
+		if (aux)
+			*piix4_smba |= 0x20;
+	} else {
+		*smb_en_status = smba_en_lo & 0x01;
+		*piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0;
+	}
+
+	if (!*smb_en_status) {
+		dev_err(&PIIX4_dev->dev,
+			"SMBus Host Controller not enabled!\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
 static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
 			     const struct pci_device_id *id, u8 aux)
 {
-	unsigned short piix4_smba;
-	u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status, port_sel;
+	u8 smb_en, smb_en_status, port_sel;
 	u8 i2ccfg, i2ccfg_offset = 0x10;
+	unsigned short piix4_smba;
 	int retval;
 
 	/* SB800 and later SMBus does not support forcing address */
@@ -310,33 +350,12 @@  static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
 	else
 		smb_en = (aux) ? 0x28 : 0x2c;
 
-	retval = piix4_sb800_region_request(&PIIX4_dev->dev);
+	retval = piix4_setup_sb800_smba(PIIX4_dev, smb_en, aux, &smb_en_status,
+					&piix4_smba);
+
 	if (retval)
 		return retval;
 
-	outb_p(smb_en, SB800_PIIX4_SMB_IDX);
-	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
-	outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
-	smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
-
-	piix4_sb800_region_release(&PIIX4_dev->dev);
-
-	if (!smb_en) {
-		smb_en_status = smba_en_lo & 0x10;
-		piix4_smba = smba_en_hi << 8;
-		if (aux)
-			piix4_smba |= 0x20;
-	} else {
-		smb_en_status = smba_en_lo & 0x01;
-		piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0;
-	}
-
-	if (!smb_en_status) {
-		dev_err(&PIIX4_dev->dev,
-			"SMBus Host Controller not enabled!\n");
-		return -ENODEV;
-	}
-
 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
 		return -ENODEV;