From e57718f522d3324bf9343200fabeb316700f49ed Mon Sep 17 00:00:00 2001 From: Vladimir Serbinenko Date: Mon, 27 Jan 2014 23:48:27 +0100 Subject: bd82x6x: Add smbus_write_byte Change-Id: Iaab076cc014a1ee463866c243636f4f71798ddc4 Signed-off-by: Vladimir Serbinenko Reviewed-on: http://review.coreboot.org/4838 Tested-by: build bot (Jenkins) Reviewed-by: Rudolf Marek --- src/southbridge/intel/bd82x6x/smbus.c | 57 +++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) (limited to 'src/southbridge/intel/bd82x6x') diff --git a/src/southbridge/intel/bd82x6x/smbus.c b/src/southbridge/intel/bd82x6x/smbus.c index 4786d8b6c9..6d4e457db7 100644 --- a/src/southbridge/intel/bd82x6x/smbus.c +++ b/src/southbridge/intel/bd82x6x/smbus.c @@ -58,8 +58,65 @@ static int lsmbus_read_byte(device_t dev, u8 address) return do_smbus_read_byte(res->base, device, address); } +static int do_smbus_write_byte(unsigned smbus_base, unsigned device, unsigned address, unsigned data) +{ + unsigned char global_status_register; + + if (smbus_wait_until_ready(smbus_base) < 0) + return SMBUS_WAIT_UNTIL_READY_TIMEOUT; + + /* Setup transaction */ + /* Disable interrupts */ + outb(inb(smbus_base + SMBHSTCTL) & (~1), smbus_base + SMBHSTCTL); + /* Set the device I'm talking too */ + outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD); + /* Set the command/address... */ + outb(address & 0xff, smbus_base + SMBHSTCMD); + /* Set up for a byte data read */ + outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | (0x2 << 2), + (smbus_base + SMBHSTCTL)); + /* Clear any lingering errors, so the transaction will run */ + outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT); + + /* Clear the data byte... */ + outb(data, smbus_base + SMBHSTDAT0); + + /* Start the command */ + outb((inb(smbus_base + SMBHSTCTL) | 0x40), + smbus_base + SMBHSTCTL); + + /* Poll for transaction completion */ + if (smbus_wait_until_done(smbus_base) < 0) + return SMBUS_WAIT_UNTIL_DONE_TIMEOUT; + + global_status_register = inb(smbus_base + SMBHSTSTAT); + + /* Ignore the "In Use" status... */ + global_status_register &= ~(3 << 5); + + /* Read results of transaction */ + if (global_status_register != (1 << 1)) + return SMBUS_ERROR; + + return 0; +} + +static int lsmbus_write_byte(device_t dev, u8 address, u8 val) +{ + u16 device; + struct resource *res; + struct bus *pbus; + + device = dev->path.i2c.device; + pbus = get_pbus_smbus(dev); + res = find_resource(pbus->dev, 0x20); + + return do_smbus_write_byte(res->base, device, address, val); +} + static struct smbus_bus_operations lops_smbus_bus = { .read_byte = lsmbus_read_byte, + .write_byte = lsmbus_write_byte, }; static void smbus_set_subsystem(device_t dev, unsigned vendor, unsigned device) -- cgit v1.2.3