u-boot/drivers/i2c/muxes/i2c-mux-uclass.c

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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*/
#define LOG_CATEGORY UCLASS_I2C_MUX
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <i2c.h>
#include <log.h>
#include <malloc.h>
#include <dm/lists.h>
#include <dm/root.h>
/**
* struct i2c_mux: Information the uclass stores about an I2C mux
*
* @selected: Currently selected mux, or -1 for none
* @i2c_bus: I2C bus to use for communcation
*/
struct i2c_mux {
int selected;
struct udevice *i2c_bus;
};
/**
* struct i2c_mux_bus: Information about each bus the mux controls
*
* @channel: Channel number used to select this bus
*/
struct i2c_mux_bus {
uint channel;
};
/* Find out the mux channel number */
static int i2c_mux_child_post_bind(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_plat(dev);
int channel;
channel = dev_read_u32_default(dev, "reg", -1);
if (channel < 0)
return -EINVAL;
plat->channel = channel;
return 0;
}
/* Find the I2C buses selected by this mux */
static int i2c_mux_post_bind(struct udevice *mux)
{
ofnode node;
int ret;
debug("%s: %s\n", __func__, mux->name);
/*
* There is no compatible string in the sub-nodes, so we must manually
* bind these
*/
dev_for_each_subnode(node, mux) {
struct udevice *dev;
const char *name;
i2c: mux: Generate longer i2c mux name For !DM case busses are listed as ZynqMP> i2c bus Bus 0: zynq_0 Bus 1: zynq_0->PCA9544A@0x75:0 Bus 2: zynq_0->PCA9544A@0x75:1 Bus 3: zynq_0->PCA9544A@0x75:2 Bus 4: zynq_1 Bus 5: zynq_1->PCA9548@0x74:0 Bus 6: zynq_1->PCA9548@0x74:1 Bus 7: zynq_1->PCA9548@0x74:2 Bus 8: zynq_1->PCA9548@0x74:3 Bus 9: zynq_1->PCA9548@0x74:4 Bus 10: zynq_1->PCA9548@0x75:0 Bus 11: zynq_1->PCA9548@0x75:1 Bus 12: zynq_1->PCA9548@0x75:2 Bus 13: zynq_1->PCA9548@0x75:3 Bus 14: zynq_1->PCA9548@0x75:4 Bus 15: zynq_1->PCA9548@0x75:5 Bus 16: zynq_1->PCA9548@0x75:6 Bus 17: zynq_1->PCA9548@0x75:7 where is exactly describing i2c bus topology. By moving to DM case i2c mux buses are using names from DT and because i2c-muxes describing sub busses with the same names like i2c@0, etc it is hard to identify which bus is where. Linux is adding topology information to i2c-mux busses to identify them better. This patch is doing the same and composing bus name with topology information. When patch is applied with topology information on zcu102-revA. ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 2: i2c@ff020000->i2c-mux@75->i2c@0 Bus 3: i2c@ff020000->i2c-mux@75->i2c@1 Bus 4: i2c@ff020000->i2c-mux@75->i2c@2 Bus 1: i2c@ff030000 (active 1) 74: i2c-mux@74, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 5: i2c@ff030000->i2c-mux@74->i2c@0 (active 5) 54: eeprom@54, offset len 1, flags 0 Bus 6: i2c@ff030000->i2c-mux@74->i2c@1 Bus 7: i2c@ff030000->i2c-mux@74->i2c@2 Bus 8: i2c@ff030000->i2c-mux@74->i2c@3 Bus 9: i2c@ff030000->i2c-mux@74->i2c@4 Bus 10: i2c@ff030000->i2c-mux@75->i2c@0 Bus 11: i2c@ff030000->i2c-mux@75->i2c@1 Bus 12: i2c@ff030000->i2c-mux@75->i2c@2 Bus 13: i2c@ff030000->i2c-mux@75->i2c@3 Bus 14: i2c@ff030000->i2c-mux@75->i2c@4 Bus 15: i2c@ff030000->i2c-mux@75->i2c@5 Bus 16: i2c@ff030000->i2c-mux@75->i2c@6 Bus 17: i2c@ff030000->i2c-mux@75->i2c@7 Behavior before the patch is applied. ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 2: i2c@0 Bus 3: i2c@1 Bus 4: i2c@2 Bus 1: i2c@ff030000 (active 1) 74: i2c-mux@74, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 5: i2c@0 (active 5) 54: eeprom@54, offset len 1, flags 0 Bus 6: i2c@1 Bus 7: i2c@2 Bus 8: i2c@3 Bus 9: i2c@4 Bus 10: i2c@0 Bus 11: i2c@1 Bus 12: i2c@2 Bus 13: i2c@3 Bus 14: i2c@4 Bus 15: i2c@5 Bus 16: i2c@6 Bus 17: i2c@7 Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Heiko Schocher <hs@denx.de>
2019-01-31 15:31:03 +00:00
const char *arrow = "->";
char *full_name;
int parent_name_len, arrow_len, mux_name_len, name_len;
name = ofnode_get_name(node);
i2c: mux: Generate longer i2c mux name For !DM case busses are listed as ZynqMP> i2c bus Bus 0: zynq_0 Bus 1: zynq_0->PCA9544A@0x75:0 Bus 2: zynq_0->PCA9544A@0x75:1 Bus 3: zynq_0->PCA9544A@0x75:2 Bus 4: zynq_1 Bus 5: zynq_1->PCA9548@0x74:0 Bus 6: zynq_1->PCA9548@0x74:1 Bus 7: zynq_1->PCA9548@0x74:2 Bus 8: zynq_1->PCA9548@0x74:3 Bus 9: zynq_1->PCA9548@0x74:4 Bus 10: zynq_1->PCA9548@0x75:0 Bus 11: zynq_1->PCA9548@0x75:1 Bus 12: zynq_1->PCA9548@0x75:2 Bus 13: zynq_1->PCA9548@0x75:3 Bus 14: zynq_1->PCA9548@0x75:4 Bus 15: zynq_1->PCA9548@0x75:5 Bus 16: zynq_1->PCA9548@0x75:6 Bus 17: zynq_1->PCA9548@0x75:7 where is exactly describing i2c bus topology. By moving to DM case i2c mux buses are using names from DT and because i2c-muxes describing sub busses with the same names like i2c@0, etc it is hard to identify which bus is where. Linux is adding topology information to i2c-mux busses to identify them better. This patch is doing the same and composing bus name with topology information. When patch is applied with topology information on zcu102-revA. ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 2: i2c@ff020000->i2c-mux@75->i2c@0 Bus 3: i2c@ff020000->i2c-mux@75->i2c@1 Bus 4: i2c@ff020000->i2c-mux@75->i2c@2 Bus 1: i2c@ff030000 (active 1) 74: i2c-mux@74, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 5: i2c@ff030000->i2c-mux@74->i2c@0 (active 5) 54: eeprom@54, offset len 1, flags 0 Bus 6: i2c@ff030000->i2c-mux@74->i2c@1 Bus 7: i2c@ff030000->i2c-mux@74->i2c@2 Bus 8: i2c@ff030000->i2c-mux@74->i2c@3 Bus 9: i2c@ff030000->i2c-mux@74->i2c@4 Bus 10: i2c@ff030000->i2c-mux@75->i2c@0 Bus 11: i2c@ff030000->i2c-mux@75->i2c@1 Bus 12: i2c@ff030000->i2c-mux@75->i2c@2 Bus 13: i2c@ff030000->i2c-mux@75->i2c@3 Bus 14: i2c@ff030000->i2c-mux@75->i2c@4 Bus 15: i2c@ff030000->i2c-mux@75->i2c@5 Bus 16: i2c@ff030000->i2c-mux@75->i2c@6 Bus 17: i2c@ff030000->i2c-mux@75->i2c@7 Behavior before the patch is applied. ZynqMP> i2c bus Bus 0: i2c@ff020000 20: gpio@20, offset len 1, flags 0 21: gpio@21, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 2: i2c@0 Bus 3: i2c@1 Bus 4: i2c@2 Bus 1: i2c@ff030000 (active 1) 74: i2c-mux@74, offset len 1, flags 0 75: i2c-mux@75, offset len 1, flags 0 Bus 5: i2c@0 (active 5) 54: eeprom@54, offset len 1, flags 0 Bus 6: i2c@1 Bus 7: i2c@2 Bus 8: i2c@3 Bus 9: i2c@4 Bus 10: i2c@0 Bus 11: i2c@1 Bus 12: i2c@2 Bus 13: i2c@3 Bus 14: i2c@4 Bus 15: i2c@5 Bus 16: i2c@6 Bus 17: i2c@7 Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Simon Glass <sjg@chromium.org> Reviewed-by: Heiko Schocher <hs@denx.de>
2019-01-31 15:31:03 +00:00
/* Calculate lenghts of strings */
parent_name_len = strlen(mux->parent->name);
arrow_len = strlen(arrow);
mux_name_len = strlen(mux->name);
name_len = strlen(name);
full_name = calloc(1, parent_name_len + arrow_len +
mux_name_len + arrow_len + name_len + 1);
if (!full_name)
return -ENOMEM;
/* Compose bus name */
strcat(full_name, mux->parent->name);
strcat(full_name, arrow);
strcat(full_name, mux->name);
strcat(full_name, arrow);
strcat(full_name, name);
ret = device_bind_driver_to_node(mux, "i2c_mux_bus_drv",
full_name, node, &dev);
debug(" - bind ret=%d, %s, seq %d\n", ret,
dev ? dev->name : NULL, dev_seq(dev));
if (ret)
return ret;
}
return 0;
}
/* Set up the mux ready for use */
static int i2c_mux_post_probe(struct udevice *mux)
{
struct i2c_mux *priv = dev_get_uclass_priv(mux);
int ret;
debug("%s: %s\n", __func__, mux->name);
priv->selected = -1;
/* if parent is of i2c uclass already, we'll take that, otherwise
* look if we find an i2c-parent phandle
*/
if (UCLASS_I2C == device_get_uclass_id(mux->parent)) {
priv->i2c_bus = dev_get_parent(mux);
debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus,
priv->i2c_bus->name);
return 0;
}
ret = uclass_get_device_by_phandle(UCLASS_I2C, mux, "i2c-parent",
&priv->i2c_bus);
if (ret)
return ret;
debug("%s: bus=%p/%s\n", __func__, priv->i2c_bus, priv->i2c_bus->name);
return 0;
}
int i2c_mux_select(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_plat(dev);
struct udevice *mux = dev->parent;
struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
if (!ops->select)
return -ENOSYS;
return ops->select(mux, dev, plat->channel);
}
int i2c_mux_deselect(struct udevice *dev)
{
struct i2c_mux_bus *plat = dev_get_parent_plat(dev);
struct udevice *mux = dev->parent;
struct i2c_mux_ops *ops = i2c_mux_get_ops(mux);
if (!ops->deselect)
return -ENOSYS;
return ops->deselect(mux, dev, plat->channel);
}
static int i2c_mux_bus_set_bus_speed(struct udevice *dev, unsigned int speed)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
int ret, ret2;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = dm_i2c_set_bus_speed(priv->i2c_bus, speed);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static int i2c_mux_bus_probe(struct udevice *dev, uint chip_addr,
uint chip_flags)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
int ret, ret2;
debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
if (!ops->probe_chip)
return -ENOSYS;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = ops->probe_chip(priv->i2c_bus, chip_addr, chip_flags);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static int i2c_mux_bus_xfer(struct udevice *dev, struct i2c_msg *msg,
int nmsgs)
{
struct udevice *mux = dev->parent;
struct i2c_mux *priv = dev_get_uclass_priv(mux);
struct dm_i2c_ops *ops = i2c_get_ops(priv->i2c_bus);
int ret, ret2;
debug("%s: %s, bus %s\n", __func__, dev->name, priv->i2c_bus->name);
if (!ops->xfer)
return -ENOSYS;
ret = i2c_mux_select(dev);
if (ret)
return ret;
ret = ops->xfer(priv->i2c_bus, msg, nmsgs);
ret2 = i2c_mux_deselect(dev);
return ret ? ret : ret2;
}
static const struct dm_i2c_ops i2c_mux_bus_ops = {
.xfer = i2c_mux_bus_xfer,
.probe_chip = i2c_mux_bus_probe,
.set_bus_speed = i2c_mux_bus_set_bus_speed,
};
U_BOOT_DRIVER(i2c_mux_bus) = {
.name = "i2c_mux_bus_drv",
.id = UCLASS_I2C,
.ops = &i2c_mux_bus_ops,
};
UCLASS_DRIVER(i2c_mux) = {
.id = UCLASS_I2C_MUX,
.name = "i2c_mux",
.post_bind = i2c_mux_post_bind,
.post_probe = i2c_mux_post_probe,
.per_device_auto = sizeof(struct i2c_mux),
.per_child_plat_auto = sizeof(struct i2c_mux_bus),
.child_post_bind = i2c_mux_child_post_bind,
};