Revision e9338abf0e186336022293d2e454c106761f262b authored by Linus Torvalds on 15 July 2021, 20:57:31 UTC, committed by Linus Torvalds on 15 July 2021, 20:57:31 UTC
Pull fallthrough fixes from Gustavo Silva: "This fixes many fall-through warnings when building with Clang and -Wimplicit-fallthrough, and also enables -Wimplicit-fallthrough for Clang, globally. It's also important to notice that since we have adopted the use of the pseudo-keyword macro fallthrough, we also want to avoid having more /* fall through */ comments being introduced. Contrary to GCC, Clang doesn't recognize any comments as implicit fall-through markings when the -Wimplicit-fallthrough option is enabled. So, in order to avoid having more comments being introduced, we use the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang, will cause a warning in case a code comment is intended to be used as a fall-through marking. The patch for Makefile also enforces this. We had almost 4,000 of these issues for Clang in the beginning, and there might be a couple more out there when building some architectures with certain configurations. However, with the recent fixes I think we are in good shape and it is now possible to enable the warning for Clang" * tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits) Makefile: Enable -Wimplicit-fallthrough for Clang powerpc/smp: Fix fall-through warning for Clang dmaengine: mpc512x: Fix fall-through warning for Clang usb: gadget: fsl_qe_udc: Fix fall-through warning for Clang powerpc/powernv: Fix fall-through warning for Clang MIPS: Fix unreachable code issue MIPS: Fix fall-through warnings for Clang ASoC: Mediatek: MT8183: Fix fall-through warning for Clang power: supply: Fix fall-through warnings for Clang dmaengine: ti: k3-udma: Fix fall-through warning for Clang s390: Fix fall-through warnings for Clang dmaengine: ipu: Fix fall-through warning for Clang iommu/arm-smmu-v3: Fix fall-through warning for Clang mmc: jz4740: Fix fall-through warning for Clang PCI: Fix fall-through warning for Clang scsi: libsas: Fix fall-through warning for Clang video: fbdev: Fix fall-through warning for Clang math-emu: Fix fall-through warning cpufreq: Fix fall-through warning for Clang drm/msm: Fix fall-through warning in msm_gem_new_impl() ...
msg2638.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for MStar msg2638 touchscreens
*
* Copyright (c) 2021 Vincent Knecht <vincent.knecht@mailoo.org>
*
* Checksum and IRQ handler based on mstar_drv_common.c and
* mstar_drv_mutual_fw_control.c
* Copyright (c) 2006-2012 MStar Semiconductor, Inc.
*
* Driver structure based on zinitix.c by Michael Srba <Michael.Srba@seznam.cz>
*/
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#define MODE_DATA_RAW 0x5A
#define MAX_SUPPORTED_FINGER_NUM 5
#define CHIP_ON_DELAY_MS 15
#define FIRMWARE_ON_DELAY_MS 50
#define RESET_DELAY_MIN_US 10000
#define RESET_DELAY_MAX_US 11000
struct packet {
u8 xy_hi; /* higher bits of x and y coordinates */
u8 x_low;
u8 y_low;
u8 pressure;
};
struct touch_event {
u8 mode;
struct packet pkt[MAX_SUPPORTED_FINGER_NUM];
u8 proximity;
u8 checksum;
};
struct msg2638_ts_data {
struct i2c_client *client;
struct input_dev *input_dev;
struct touchscreen_properties prop;
struct regulator_bulk_data supplies[2];
struct gpio_desc *reset_gpiod;
};
static u8 msg2638_checksum(u8 *data, u32 length)
{
s32 sum = 0;
u32 i;
for (i = 0; i < length; i++)
sum += data[i];
return (u8)((-sum) & 0xFF);
}
static irqreturn_t msg2638_ts_irq_handler(int irq, void *msg2638_handler)
{
struct msg2638_ts_data *msg2638 = msg2638_handler;
struct i2c_client *client = msg2638->client;
struct input_dev *input = msg2638->input_dev;
struct touch_event touch_event;
u32 len = sizeof(touch_event);
struct i2c_msg msg[] = {
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = sizeof(touch_event),
.buf = (u8 *)&touch_event,
},
};
struct packet *p;
u16 x, y;
int ret;
int i;
ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret != ARRAY_SIZE(msg)) {
dev_err(&client->dev,
"Failed I2C transfer in irq handler: %d\n",
ret < 0 ? ret : -EIO);
goto out;
}
if (touch_event.mode != MODE_DATA_RAW)
goto out;
if (msg2638_checksum((u8 *)&touch_event, len - 1) !=
touch_event.checksum) {
dev_err(&client->dev, "Failed checksum!\n");
goto out;
}
for (i = 0; i < MAX_SUPPORTED_FINGER_NUM; i++) {
p = &touch_event.pkt[i];
/* Ignore non-pressed finger data */
if (p->xy_hi == 0xFF && p->x_low == 0xFF && p->y_low == 0xFF)
continue;
x = (((p->xy_hi & 0xF0) << 4) | p->x_low);
y = (((p->xy_hi & 0x0F) << 8) | p->y_low);
input_mt_slot(input, i);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
touchscreen_report_pos(input, &msg2638->prop, x, y, true);
}
input_mt_sync_frame(msg2638->input_dev);
input_sync(msg2638->input_dev);
out:
return IRQ_HANDLED;
}
static void msg2638_reset(struct msg2638_ts_data *msg2638)
{
gpiod_set_value_cansleep(msg2638->reset_gpiod, 1);
usleep_range(RESET_DELAY_MIN_US, RESET_DELAY_MAX_US);
gpiod_set_value_cansleep(msg2638->reset_gpiod, 0);
msleep(FIRMWARE_ON_DELAY_MS);
}
static int msg2638_start(struct msg2638_ts_data *msg2638)
{
int error;
error = regulator_bulk_enable(ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(&msg2638->client->dev,
"Failed to enable regulators: %d\n", error);
return error;
}
msleep(CHIP_ON_DELAY_MS);
msg2638_reset(msg2638);
enable_irq(msg2638->client->irq);
return 0;
}
static int msg2638_stop(struct msg2638_ts_data *msg2638)
{
int error;
disable_irq(msg2638->client->irq);
error = regulator_bulk_disable(ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(&msg2638->client->dev,
"Failed to disable regulators: %d\n", error);
return error;
}
return 0;
}
static int msg2638_input_open(struct input_dev *dev)
{
struct msg2638_ts_data *msg2638 = input_get_drvdata(dev);
return msg2638_start(msg2638);
}
static void msg2638_input_close(struct input_dev *dev)
{
struct msg2638_ts_data *msg2638 = input_get_drvdata(dev);
msg2638_stop(msg2638);
}
static int msg2638_init_input_dev(struct msg2638_ts_data *msg2638)
{
struct device *dev = &msg2638->client->dev;
struct input_dev *input_dev;
int error;
input_dev = devm_input_allocate_device(dev);
if (!input_dev) {
dev_err(dev, "Failed to allocate input device.\n");
return -ENOMEM;
}
input_set_drvdata(input_dev, msg2638);
msg2638->input_dev = input_dev;
input_dev->name = "MStar TouchScreen";
input_dev->phys = "input/ts";
input_dev->id.bustype = BUS_I2C;
input_dev->open = msg2638_input_open;
input_dev->close = msg2638_input_close;
input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
touchscreen_parse_properties(input_dev, true, &msg2638->prop);
if (!msg2638->prop.max_x || !msg2638->prop.max_y) {
dev_err(dev, "touchscreen-size-x and/or touchscreen-size-y not set in properties\n");
return -EINVAL;
}
error = input_mt_init_slots(input_dev, MAX_SUPPORTED_FINGER_NUM,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(dev, "Failed to initialize MT slots: %d\n", error);
return error;
}
error = input_register_device(input_dev);
if (error) {
dev_err(dev, "Failed to register input device: %d\n", error);
return error;
}
return 0;
}
static int msg2638_ts_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct msg2638_ts_data *msg2638;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(dev, "Failed to assert adapter's support for plain I2C.\n");
return -ENXIO;
}
msg2638 = devm_kzalloc(dev, sizeof(*msg2638), GFP_KERNEL);
if (!msg2638)
return -ENOMEM;
msg2638->client = client;
i2c_set_clientdata(client, msg2638);
msg2638->supplies[0].supply = "vdd";
msg2638->supplies[1].supply = "vddio";
error = devm_regulator_bulk_get(dev, ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(dev, "Failed to get regulators: %d\n", error);
return error;
}
msg2638->reset_gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(msg2638->reset_gpiod)) {
error = PTR_ERR(msg2638->reset_gpiod);
dev_err(dev, "Failed to request reset GPIO: %d\n", error);
return error;
}
error = msg2638_init_input_dev(msg2638);
if (error) {
dev_err(dev, "Failed to initialize input device: %d\n", error);
return error;
}
error = devm_request_threaded_irq(dev, client->irq,
NULL, msg2638_ts_irq_handler,
IRQF_ONESHOT | IRQF_NO_AUTOEN,
client->name, msg2638);
if (error) {
dev_err(dev, "Failed to request IRQ: %d\n", error);
return error;
}
return 0;
}
static int __maybe_unused msg2638_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct msg2638_ts_data *msg2638 = i2c_get_clientdata(client);
mutex_lock(&msg2638->input_dev->mutex);
if (input_device_enabled(msg2638->input_dev))
msg2638_stop(msg2638);
mutex_unlock(&msg2638->input_dev->mutex);
return 0;
}
static int __maybe_unused msg2638_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct msg2638_ts_data *msg2638 = i2c_get_clientdata(client);
int ret = 0;
mutex_lock(&msg2638->input_dev->mutex);
if (input_device_enabled(msg2638->input_dev))
ret = msg2638_start(msg2638);
mutex_unlock(&msg2638->input_dev->mutex);
return ret;
}
static SIMPLE_DEV_PM_OPS(msg2638_pm_ops, msg2638_suspend, msg2638_resume);
static const struct of_device_id msg2638_of_match[] = {
{ .compatible = "mstar,msg2638" },
{ }
};
MODULE_DEVICE_TABLE(of, msg2638_of_match);
static struct i2c_driver msg2638_ts_driver = {
.probe_new = msg2638_ts_probe,
.driver = {
.name = "MStar-TS",
.pm = &msg2638_pm_ops,
.of_match_table = msg2638_of_match,
},
};
module_i2c_driver(msg2638_ts_driver);
MODULE_AUTHOR("Vincent Knecht <vincent.knecht@mailoo.org>");
MODULE_DESCRIPTION("MStar MSG2638 touchscreen driver");
MODULE_LICENSE("GPL v2");
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