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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/input/touchscreen/ad7879-spi.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/touchscreen/ad7879-spi.c')
-rw-r--r--drivers/input/touchscreen/ad7879-spi.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/ad7879-spi.c b/drivers/input/touchscreen/ad7879-spi.c
new file mode 100644
index 000000000..50e889846
--- /dev/null
+++ b/drivers/input/touchscreen/ad7879-spi.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AD7879/AD7889 touchscreen (SPI bus)
+ *
+ * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
+ */
+
+#include <linux/input.h> /* BUS_SPI */
+#include <linux/pm.h>
+#include <linux/spi/spi.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include "ad7879.h"
+
+#define AD7879_DEVID 0x7A /* AD7879/AD7889 */
+
+#define MAX_SPI_FREQ_HZ 5000000
+
+#define AD7879_CMD_MAGIC 0xE0
+#define AD7879_CMD_READ BIT(2)
+
+static const struct regmap_config ad7879_spi_regmap_config = {
+ .reg_bits = 16,
+ .val_bits = 16,
+ .max_register = 15,
+ .read_flag_mask = AD7879_CMD_MAGIC | AD7879_CMD_READ,
+ .write_flag_mask = AD7879_CMD_MAGIC,
+};
+
+static int ad7879_spi_probe(struct spi_device *spi)
+{
+ struct regmap *regmap;
+
+ /* don't exceed max specified SPI CLK frequency */
+ if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
+ dev_err(&spi->dev, "SPI CLK %d Hz?\n", spi->max_speed_hz);
+ return -EINVAL;
+ }
+
+ regmap = devm_regmap_init_spi(spi, &ad7879_spi_regmap_config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ return ad7879_probe(&spi->dev, regmap, spi->irq, BUS_SPI, AD7879_DEVID);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id ad7879_spi_dt_ids[] = {
+ { .compatible = "adi,ad7879", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad7879_spi_dt_ids);
+#endif
+
+static struct spi_driver ad7879_spi_driver = {
+ .driver = {
+ .name = "ad7879",
+ .pm = &ad7879_pm_ops,
+ .of_match_table = of_match_ptr(ad7879_spi_dt_ids),
+ },
+ .probe = ad7879_spi_probe,
+};
+
+module_spi_driver(ad7879_spi_driver);
+
+MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
+MODULE_DESCRIPTION("AD7879(-1) touchscreen SPI bus driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ad7879");