[PATCH 5.15 008/132] i2c: piix4: Move SMBus port selection into function

Greg Kroah-Hartman
2022-05-23T17:30:39Z

From: Terry Bowman <terry.bowman@amd.com>

commit fbafbd51bff52cb3a920fd98d4dae2a78dd433d0 upstream.

Move port selection code into a separate function. Refactor is in
preparation for following MMIO changes.

Signed-off-by: Terry Bowman <terry.bowman@amd.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Cc: Mario Limonciello <Mario.Limonciello@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/i2c/busses/i2c-piix4.c | 27 +++++++++++++++++----------
1 file changed, 17 insertions(+), 10 deletions(-)

--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -698,6 +698,20 @@ static void piix4_imc_wakeup(void)
release_region(KERNCZ_IMC_IDX, 2);
}

+static int piix4_sb800_port_sel(u8 port)
+{
+ u8 smba_en_lo, val;
+
+ outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
+ smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
+
+ val = (smba_en_lo & ~piix4_port_mask_sb800) | port;
+ if (smba_en_lo != val)
+ outb_p(val, SB800_PIIX4_SMB_IDX + 1);
+
+ return (smba_en_lo & piix4_port_mask_sb800);
+}
+
/*
* Handles access to multiple SMBus ports on the SB800.
* The port is selected by bits 2:1 of the smb_en register (0x2c).
@@ -714,8 +728,7 @@ static s32 piix4_access_sb800(struct i2c
unsigned short piix4_smba = adapdata->smba;
int retries = MAX_TIMEOUT;
int smbslvcnt;
- u8 smba_en_lo;
- u8 port;
+ u8 prev_port;
int retval;

retval = piix4_sb800_region_request(&adap->dev);
@@ -775,18 +788,12 @@ static s32 piix4_access_sb800(struct i2c
}
}

- outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
- smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
-
- port = adapdata->port;
- if ((smba_en_lo & piix4_port_mask_sb800) != port)
- outb_p((smba_en_lo & ~piix4_port_mask_sb800) | port,
- SB800_PIIX4_SMB_IDX + 1);
+ prev_port = piix4_sb800_port_sel(adapdata->port);

retval = piix4_access(adap, addr, flags, read_write,
command, size, data);

- outb_p(smba_en_lo, SB800_PIIX4_SMB_IDX + 1);
+ piix4_sb800_port_sel(prev_port);

/* Release the semaphore */
outb_p(smbslvcnt | 0x20, SMBSLVCNT);