From a5969cabbb4660eab42b6ef0412cbbd1200cf14d Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Sat, 12 Oct 2024 07:10:09 +0000
Subject: [PATCH] 修改led为gpio
---
kernel/drivers/i2c/muxes/i2c-mux-pca954x.c | 201 +++++++++++++++++++++++++++++++++-----------------
1 files changed, 132 insertions(+), 69 deletions(-)
diff --git a/kernel/drivers/i2c/muxes/i2c-mux-pca954x.c b/kernel/drivers/i2c/muxes/i2c-mux-pca954x.c
index 24bd927..4ad6657 100644
--- a/kernel/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/kernel/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -1,10 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* I2C multiplexer
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
*
- * This module supports the PCA954x and PCA954x series of I2C multiplexer/switch
+ * This module supports the PCA954x and PCA984x series of I2C multiplexer/switch
* chips made by NXP Semiconductors.
* This includes the:
* PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547,
@@ -29,10 +30,6 @@
* i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com>
* and
* pca9540.c from Jean Delvare <jdelvare@suse.de>.
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
*/
#include <linux/device.h>
@@ -43,13 +40,11 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/of_irq.h>
-#include <linux/platform_data/pca954x.h>
#include <linux/pm.h>
+#include <linux/property.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
+#include <dt-bindings/mux/mux.h>
#define PCA954X_MAX_NCHANS 8
@@ -85,7 +80,9 @@
const struct chip_desc *chip;
u8 last_chan; /* last register value */
- u8 deselect;
+ /* MUX_IDLE_AS_IS, MUX_IDLE_DISCONNECT or >= 0 for channel */
+ s32 idle_state;
+
struct i2c_client *client;
struct irq_domain *irq;
@@ -196,7 +193,6 @@
};
MODULE_DEVICE_TABLE(i2c, pca954x_id);
-#ifdef CONFIG_OF
static const struct of_device_id pca954x_of_match[] = {
{ .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
{ .compatible = "nxp,pca9542", .data = &chips[pca_9542] },
@@ -213,7 +209,6 @@
{}
};
MODULE_DEVICE_TABLE(of, pca954x_of_match);
-#endif
/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
for this as they will try to lock adapter a second time */
@@ -227,20 +222,23 @@
I2C_SMBUS_BYTE, &dummy);
}
+static u8 pca954x_regval(struct pca954x *data, u8 chan)
+{
+ /* We make switches look like muxes, not sure how to be smarter. */
+ if (data->chip->muxtype == pca954x_ismux)
+ return chan | data->chip->enable;
+ else
+ return 1 << chan;
+}
+
static int pca954x_select_chan(struct i2c_mux_core *muxc, u32 chan)
{
struct pca954x *data = i2c_mux_priv(muxc);
struct i2c_client *client = data->client;
- const struct chip_desc *chip = data->chip;
u8 regval;
int ret = 0;
- /* we make switches look like muxes, not sure how to be smarter */
- if (chip->muxtype == pca954x_ismux)
- regval = chan | chip->enable;
- else
- regval = 1 << chan;
-
+ regval = pca954x_regval(data, chan);
/* Only select the channel if its different from the last channel */
if (data->last_chan != regval) {
ret = pca954x_reg_write(muxc->parent, client, regval);
@@ -254,33 +252,86 @@
{
struct pca954x *data = i2c_mux_priv(muxc);
struct i2c_client *client = data->client;
+ s32 idle_state;
- if (!(data->deselect & (1 << chan)))
- return 0;
+ idle_state = READ_ONCE(data->idle_state);
+ if (idle_state >= 0)
+ /* Set the mux back to a predetermined channel */
+ return pca954x_select_chan(muxc, idle_state);
- /* Deselect active channel */
- data->last_chan = 0;
- return pca954x_reg_write(muxc->parent, client, data->last_chan);
+ if (idle_state == MUX_IDLE_DISCONNECT) {
+ /* Deselect active channel */
+ data->last_chan = 0;
+ return pca954x_reg_write(muxc->parent, client,
+ data->last_chan);
+ }
+
+ /* otherwise leave as-is */
+
+ return 0;
}
+
+static ssize_t idle_state_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
+
+ return sprintf(buf, "%d\n", READ_ONCE(data->idle_state));
+}
+
+static ssize_t idle_state_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ struct pca954x *data = i2c_mux_priv(muxc);
+ int val;
+ int ret;
+
+ ret = kstrtoint(buf, 0, &val);
+ if (ret < 0)
+ return ret;
+
+ if (val != MUX_IDLE_AS_IS && val != MUX_IDLE_DISCONNECT &&
+ (val < 0 || val >= data->chip->nchans))
+ return -EINVAL;
+
+ i2c_lock_bus(muxc->parent, I2C_LOCK_SEGMENT);
+
+ WRITE_ONCE(data->idle_state, val);
+ /*
+ * Set the mux into a state consistent with the new
+ * idle_state.
+ */
+ if (data->last_chan || val != MUX_IDLE_DISCONNECT)
+ ret = pca954x_deselect_mux(muxc, 0);
+
+ i2c_unlock_bus(muxc->parent, I2C_LOCK_SEGMENT);
+
+ return ret < 0 ? ret : count;
+}
+
+static DEVICE_ATTR_RW(idle_state);
static irqreturn_t pca954x_irq_handler(int irq, void *dev_id)
{
struct pca954x *data = dev_id;
- unsigned int child_irq;
- int ret, i, handled = 0;
+ unsigned long pending;
+ int ret, i;
ret = i2c_smbus_read_byte(data->client);
if (ret < 0)
return IRQ_NONE;
- for (i = 0; i < data->chip->nchans; i++) {
- if (ret & BIT(PCA954X_IRQ_OFFSET + i)) {
- child_irq = irq_linear_revmap(data->irq, i);
- handle_nested_irq(child_irq);
- handled++;
- }
- }
- return handled ? IRQ_HANDLED : IRQ_NONE;
+ pending = (ret >> PCA954X_IRQ_OFFSET) & (BIT(data->chip->nchans) - 1);
+ for_each_set_bit(i, &pending, data->chip->nchans)
+ handle_nested_irq(irq_linear_revmap(data->irq, i));
+
+ return IRQ_RETVAL(pending);
}
static int pca954x_irq_set_type(struct irq_data *idata, unsigned int type)
@@ -341,21 +392,34 @@
i2c_mux_del_adapters(muxc);
}
+static int pca954x_init(struct i2c_client *client, struct pca954x *data)
+{
+ int ret;
+
+ if (data->idle_state >= 0)
+ data->last_chan = pca954x_regval(data, data->idle_state);
+ else
+ data->last_chan = 0; /* Disconnect multiplexer */
+
+ ret = i2c_smbus_write_byte(client, data->last_chan);
+ if (ret < 0)
+ data->last_chan = 0;
+
+ return ret;
+}
+
/*
* I2C init/probing/exit functions
*/
static int pca954x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
- struct pca954x_platform_data *pdata = dev_get_platdata(&client->dev);
+ struct i2c_adapter *adap = client->adapter;
struct device *dev = &client->dev;
- struct device_node *np = dev->of_node;
- bool idle_disconnect_dt;
struct gpio_desc *gpio;
- int num, force, class;
struct i2c_mux_core *muxc;
struct pca954x *data;
+ int num;
int ret;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
@@ -381,7 +445,7 @@
udelay(1);
}
- data->chip = of_device_get_match_data(dev);
+ data->chip = device_get_match_data(dev);
if (!data->chip)
data->chip = &chips[id->driver_data];
@@ -402,19 +466,23 @@
}
}
- /* Write the mux register at addr to verify
+ data->idle_state = MUX_IDLE_AS_IS;
+ if (device_property_read_u32(dev, "idle-state", &data->idle_state)) {
+ if (device_property_read_bool(dev, "i2c-mux-idle-disconnect"))
+ data->idle_state = MUX_IDLE_DISCONNECT;
+ }
+
+ /*
+ * Write the mux register at addr to verify
* that the mux is in fact present. This also
- * initializes the mux to disconnected state.
+ * initializes the mux to a channel
+ * or disconnected state.
*/
- if (i2c_smbus_write_byte(client, 0) < 0) {
+ ret = pca954x_init(client, data);
+ if (ret < 0) {
dev_warn(dev, "probe failed\n");
return -ENODEV;
}
-
- data->last_chan = 0; /* force the first selection */
-
- idle_disconnect_dt = np &&
- of_property_read_bool(np, "i2c-mux-idle-disconnect");
ret = pca954x_irq_setup(muxc);
if (ret)
@@ -422,24 +490,7 @@
/* Now create an adapter for each channel */
for (num = 0; num < data->chip->nchans; num++) {
- bool idle_disconnect_pd = false;
-
- force = 0; /* dynamic adap number */
- class = 0; /* no class by default */
- if (pdata) {
- if (num < pdata->num_modes) {
- /* force static number */
- force = pdata->modes[num].adap_id;
- class = pdata->modes[num].class;
- } else
- /* discard unconfigured channels */
- break;
- idle_disconnect_pd = pdata->modes[num].deselect_on_exit;
- }
- data->deselect |= (idle_disconnect_pd ||
- idle_disconnect_dt) << num;
-
- ret = i2c_mux_add_adapter(muxc, force, num, class);
+ ret = i2c_mux_add_adapter(muxc, 0, num, 0);
if (ret)
goto fail_cleanup;
}
@@ -452,6 +503,12 @@
if (ret)
goto fail_cleanup;
}
+
+ /*
+ * The attr probably isn't going to be needed in most cases,
+ * so don't fail completely on error.
+ */
+ device_create_file(dev, &dev_attr_idle_state);
dev_info(dev, "registered %d multiplexed busses for I2C %s %s\n",
num, data->chip->muxtype == pca954x_ismux
@@ -468,6 +525,8 @@
{
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
+ device_remove_file(&client->dev, &dev_attr_idle_state);
+
pca954x_cleanup(muxc);
return 0;
}
@@ -478,9 +537,13 @@
struct i2c_client *client = to_i2c_client(dev);
struct i2c_mux_core *muxc = i2c_get_clientdata(client);
struct pca954x *data = i2c_mux_priv(muxc);
+ int ret;
- data->last_chan = 0;
- return i2c_smbus_write_byte(client, 0);
+ ret = pca954x_init(client, data);
+ if (ret < 0)
+ dev_err(&client->dev, "failed to verify mux presence\n");
+
+ return ret;
}
#endif
@@ -490,7 +553,7 @@
.driver = {
.name = "pca954x",
.pm = &pca954x_pm,
- .of_match_table = of_match_ptr(pca954x_of_match),
+ .of_match_table = pca954x_of_match,
},
.probe = pca954x_probe,
.remove = pca954x_remove,
--
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