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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-18 11:00:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-18 11:00:00 -0700
commit2475c515d4031c494ff452508a8bf8c281ec6e56 (patch)
tree0303935bbd919ec522bf0fe02066f09b391d2b57 /drivers/iio/chemical/bme680_spi.c
parent336722eb9d9732c5a497fb6299bf38cde413592b (diff)
parente4f6a44c4aeca9eda153302abb0c14d053914f72 (diff)
Merge tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO updates from Greg KH: "Here are the big staging/iio patches for 4.19-rc1. Lots of churn here, with tons of cleanups happening in staging drivers, a removal of an old crypto driver that no one was using (skein), and the addition of some new IIO drivers. Also added was a "gasket" driver from Google that needs loads of work and the erofs filesystem. Even with adding all of the new drivers and a new filesystem, we are only adding about 1000 lines overall to the kernel linecount, which shows just how much cleanup happened, and how big the unused crypto driver was. All of these have been in the linux-next tree for a while now with no reported issues" * tag 'staging-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (903 commits) staging:rtl8192u: Remove unused macro definitions - Style staging:rtl8192u: Add spaces around '+' operator - Style staging:rtl8192u: Remove stale comment - Style staging: rtl8188eu: remove unused mp_custom_oid.h staging: fbtft: Add spaces around / - Style staging: fbtft: Erases some repetitive usage of function name - Style staging: fbtft: Adjust some empty-line problems - Style staging: fbtft: Removes one nesting level to help readability - Style staging: fbtft: Changes gamma table to define. staging: fbtft: A bit more information on dev_err. staging: fbtft: Fixes some alignment issues - Style staging: fbtft: Puts macro arguments in parenthesis to avoid precedence issues - Style staging: rtl8188eu: remove unused array dB_Invert_Table staging: rtl8188eu: remove whitespace, add missing blank line staging: rtl8188eu: use is_multicast_ether_addr in rtw_sta_mgt.c staging: rtl8188eu: remove whitespace - style staging: rtl8188eu: cleanup block comment - style staging: rtl8188eu: use is_multicast_ether_addr in rtl8188eu_xmit.c staging: rtl8188eu: use is_multicast_ether_addr in recv_linux.c staging: rtlwifi: refactor rtl_get_tcb_desc ...
Diffstat (limited to 'drivers/iio/chemical/bme680_spi.c')
-rw-r--r--drivers/iio/chemical/bme680_spi.c125
1 files changed, 125 insertions, 0 deletions
diff --git a/drivers/iio/chemical/bme680_spi.c b/drivers/iio/chemical/bme680_spi.c
new file mode 100644
index 000000000000..c9fb05e8d0b9
--- /dev/null
+++ b/drivers/iio/chemical/bme680_spi.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * BME680 - SPI Driver
+ *
+ * Copyright (C) 2018 Himanshu Jha <himanshujha199640@gmail.com>
+ */
+#include <linux/acpi.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "bme680.h"
+
+static int bme680_regmap_spi_write(void *context, const void *data,
+ size_t count)
+{
+ struct spi_device *spi = context;
+ u8 buf[2];
+
+ memcpy(buf, data, 2);
+ /*
+ * The SPI register address (= full register address without bit 7)
+ * and the write command (bit7 = RW = '0')
+ */
+ buf[0] &= ~0x80;
+
+ return spi_write_then_read(spi, buf, 2, NULL, 0);
+}
+
+static int bme680_regmap_spi_read(void *context, const void *reg,
+ size_t reg_size, void *val, size_t val_size)
+{
+ struct spi_device *spi = context;
+
+ return spi_write_then_read(spi, reg, reg_size, val, val_size);
+}
+
+static struct regmap_bus bme680_regmap_bus = {
+ .write = bme680_regmap_spi_write,
+ .read = bme680_regmap_spi_read,
+ .reg_format_endian_default = REGMAP_ENDIAN_BIG,
+ .val_format_endian_default = REGMAP_ENDIAN_BIG,
+};
+
+static int bme680_spi_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ struct regmap *regmap;
+ unsigned int val;
+ int ret;
+
+ spi->bits_per_word = 8;
+ ret = spi_setup(spi);
+ if (ret < 0) {
+ dev_err(&spi->dev, "spi_setup failed!\n");
+ return ret;
+ }
+
+ regmap = devm_regmap_init(&spi->dev, &bme680_regmap_bus,
+ &spi->dev, &bme680_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&spi->dev, "Failed to register spi regmap %d\n",
+ (int)PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ ret = regmap_write(regmap, BME680_REG_SOFT_RESET_SPI,
+ BME680_CMD_SOFTRESET);
+ if (ret < 0) {
+ dev_err(&spi->dev, "Failed to reset chip\n");
+ return ret;
+ }
+
+ /* after power-on reset, Page 0(0x80-0xFF) of spi_mem_page is active */
+ ret = regmap_read(regmap, BME680_REG_CHIP_SPI_ID, &val);
+ if (ret < 0) {
+ dev_err(&spi->dev, "Error reading SPI chip ID\n");
+ return ret;
+ }
+
+ if (val != BME680_CHIP_ID_VAL) {
+ dev_err(&spi->dev, "Wrong chip ID, got %x expected %x\n",
+ val, BME680_CHIP_ID_VAL);
+ return -ENODEV;
+ }
+ /*
+ * select Page 1 of spi_mem_page to enable access to
+ * to registers from address 0x00 to 0x7F.
+ */
+ ret = regmap_write_bits(regmap, BME680_REG_STATUS,
+ BME680_SPI_MEM_PAGE_BIT,
+ BME680_SPI_MEM_PAGE_1_VAL);
+ if (ret < 0) {
+ dev_err(&spi->dev, "failed to set page 1 of spi_mem_page\n");
+ return ret;
+ }
+
+ return bme680_core_probe(&spi->dev, regmap, id->name);
+}
+
+static const struct spi_device_id bme680_spi_id[] = {
+ {"bme680", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(spi, bme680_spi_id);
+
+static const struct acpi_device_id bme680_acpi_match[] = {
+ {"BME0680", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, bme680_acpi_match);
+
+static struct spi_driver bme680_spi_driver = {
+ .driver = {
+ .name = "bme680_spi",
+ .acpi_match_table = ACPI_PTR(bme680_acpi_match),
+ },
+ .probe = bme680_spi_probe,
+ .id_table = bme680_spi_id,
+};
+module_spi_driver(bme680_spi_driver);
+
+MODULE_AUTHOR("Himanshu Jha <himanshujha199640@gmail.com>");
+MODULE_DESCRIPTION("Bosch BME680 SPI driver");
+MODULE_LICENSE("GPL v2");