From 029dfff30cc468b3e21c2004a135d3380a8c20e6 Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Wed, 12 Jul 2017 17:59:16 +0200 Subject: i2c: Move to Linux like `struct i2c_msg` MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Our current struct for I2C segments `i2c_seg` was close to being compa- tible to the Linux version `i2c_msg`, close to being compatible to SMBus and close to being readable (e.g. what was `chip` supposed to mean?) but turned out to be hard to fix. Instead of extending it in a backwards compatible way (and not touching current controller drivers), replace it with a Linux source compatible `struct i2c_msg` and patch all the drivers and users with Coccinelle. The new `struct i2c_msg` should ease porting drivers from Linux and help to write SMBus compatible controller drivers. Beside integer type changes, the field `read` is replaced with a generic field `flags` and `chip` is renamed to `slave`. Patched with Coccinelle using the clumsy spatch below and some manual changes: * Nested struct initializers and one field access skipped by Coccinelle. * Removed assumption in the code that I2C_M_RD is 1. * In `i2c.h`, changed all occurences of `chip` to `slave`. @@ @@ -struct i2c_seg +struct i2c_msg @@ identifier msg; expression e; @@ ( struct i2c_msg msg = { - .read = 0, + .flags = 0, }; | struct i2c_msg msg = { - .read = 1, + .flags = I2C_M_RD, }; | struct i2c_msg msg = { - .chip = e, + .slave = e, }; ) @@ struct i2c_msg msg; statement S1, S2; @@ ( -if (msg.read) +if (msg.flags & I2C_M_RD) S1 else S2 | -if (msg.read) +if (msg.flags & I2C_M_RD) S1 ) @@ struct i2c_msg *msg; statement S1, S2; @@ ( -if (msg->read) +if (msg->flags & I2C_M_RD) S1 else S2 | -if (msg->read) +if (msg->flags & I2C_M_RD) S1 ) @@ struct i2c_msg msg; expression e; @@ ( -msg.read = 0; +msg.flags = 0; | -msg.read = 1; +msg.flags = I2C_M_RD; | -msg.read = e; +msg.flags = e ? I2C_M_RD : 0; | -!!(msg.read) +(msg.flags & I2C_M_RD) | -(msg.read) +(msg.flags & I2C_M_RD) ) @@ struct i2c_msg *msg; expression e; @@ ( -msg->read = 0; +msg->flags = 0; | -msg->read = 1; +msg->flags = I2C_M_RD; | -msg->read = e; +msg->flags = e ? I2C_M_RD : 0; | -!!(msg->read) +(msg->flags & I2C_M_RD) | -(msg->read) +(msg->flags & I2C_M_RD) ) @@ struct i2c_msg msg; @@ -msg.chip +msg.slave @@ struct i2c_msg *msg; expression e; @@ -msg[e].chip +msg[e].slave @ slave disable ptr_to_array @ struct i2c_msg *msg; @@ -msg->chip +msg->slave Change-Id: Ifd7cabf0a18ffd7a1def25d1d7059b713d0b7ea9 Signed-off-by: Nico Huber Reviewed-on: https://review.coreboot.org/20542 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin Reviewed-by: Werner Zeh Reviewed-by: Kyösti Mälkki Reviewed-by: Paul Menzel --- src/soc/intel/common/block/i2c/lpss_i2c.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) (limited to 'src/soc/intel/common/block/i2c') diff --git a/src/soc/intel/common/block/i2c/lpss_i2c.c b/src/soc/intel/common/block/i2c/lpss_i2c.c index 5b188f8c22..711517f6d3 100644 --- a/src/soc/intel/common/block/i2c/lpss_i2c.c +++ b/src/soc/intel/common/block/i2c/lpss_i2c.c @@ -258,7 +258,7 @@ static int lpss_i2c_wait_for_bus_idle(struct lpss_i2c_regs *regs) /* Transfer one byte of one segment, sending stop bit if requested */ static int lpss_i2c_transfer_byte(struct lpss_i2c_regs *regs, - struct i2c_seg *segment, + struct i2c_msg *segment, size_t byte, int send_stop) { struct stopwatch sw; @@ -266,7 +266,7 @@ static int lpss_i2c_transfer_byte(struct lpss_i2c_regs *regs, stopwatch_init_usecs_expire(&sw, LPSS_I2C_TIMEOUT_US); - if (!segment->read) { + if (!(segment->flags & I2C_M_RD)) { /* Write op only: Wait for FIFO not full */ while (!(read32(®s->status) & STATUS_TX_FIFO_NOT_FULL)) { if (stopwatch_expired(&sw)) { @@ -283,7 +283,7 @@ static int lpss_i2c_transfer_byte(struct lpss_i2c_regs *regs, write32(®s->cmd_data, cmd); - if (segment->read) { + if (segment->flags & I2C_M_RD) { /* Read op only: Wait for FIFO data and store it */ while (!(read32(®s->status) & STATUS_RX_FIFO_NOT_EMPTY)) { if (stopwatch_expired(&sw)) { @@ -298,7 +298,8 @@ static int lpss_i2c_transfer_byte(struct lpss_i2c_regs *regs, } /* Global I2C bus handler, defined in include/i2c.h */ -int platform_i2c_transfer(unsigned int bus, struct i2c_seg *segments, int count) +int platform_i2c_transfer(unsigned int bus, struct i2c_msg *segments, + int count) { struct stopwatch sw; struct lpss_i2c_regs *regs; @@ -325,11 +326,12 @@ int platform_i2c_transfer(unsigned int bus, struct i2c_seg *segments, int count) while (count--) { if (CONFIG_SOC_INTEL_COMMON_LPSS_I2C_DEBUG) printk(BIOS_DEBUG, "i2c %u:%02x %s %d bytes : ", - bus, segments->chip, segments->read ? "R" : "W", + bus, segments->slave, + (segments->flags & I2C_M_RD) ? "R" : "W", segments->len); /* Set target slave address */ - write32(®s->target_addr, segments->chip); + write32(®s->target_addr, segments->slave); /* Read or write each byte in segment */ for (byte = 0; byte < segments->len; byte++) { @@ -341,8 +343,9 @@ int platform_i2c_transfer(unsigned int bus, struct i2c_seg *segments, int count) if (lpss_i2c_transfer_byte(regs, segments, byte, count == 0) < 0) { printk(BIOS_ERR, "I2C %s failed: bus %u " - "addr 0x%02x\n", segments->read ? - "read" : "write", bus, segments->chip); + "addr 0x%02x\n", + (segments->flags & I2C_M_RD) ? + "read" : "write", bus, segments->slave); goto out; } } -- cgit v1.2.3