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authorTakashi Iwai <tiwai@suse.de>2019-05-06 16:14:09 +0200
committerTakashi Iwai <tiwai@suse.de>2019-05-06 16:14:34 +0200
commitd81645510ce2a140816c4cb37c45b78d810ca63f (patch)
treeedd9464900904d22a23da362bb152669480c5d26 /drivers/iio/chemical/bme680_spi.c
parent2854cd34fbab5f28a356d3667c26b7856a7b73e2 (diff)
parent378d590c494551a68a824b939c711bb9a280e9ef (diff)
Merge tag 'asoc-v5.2' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Updates for v5.2 This is a pretty huge set of changes, it's been a pretty active release all round but the big thing with this release is the Sound Open Firmware changes from Intel, providing another DSP framework for use with the DSPs in their SoCs. This one works with the firmware of the same name which is free software (unlike the previous DSP firmwares and framework) and there has been some interest in adoption by other systems already so hopefully we will see adoption by other vendors in the future. Other highlights include: - Support for MCLK/sample rate ratio setting in the generic cards. - Support for pin switches in the generic cards. - A big set of improvements to the TLV320AIC32x4 drivers from Annaliese McDermond. - New drivers for Freescale audio mixers, several Intel machines, several Mediatek machines, Meson G12A, Sound Open Firmware and Spreadtrum compressed audio and DMA devices.
Diffstat (limited to 'drivers/iio/chemical/bme680_spi.c')
-rw-r--r--drivers/iio/chemical/bme680_spi.c115
1 files changed, 78 insertions, 37 deletions
diff --git a/drivers/iio/chemical/bme680_spi.c b/drivers/iio/chemical/bme680_spi.c
index d0b7bdd3f066..3b838068a7e4 100644
--- a/drivers/iio/chemical/bme680_spi.c
+++ b/drivers/iio/chemical/bme680_spi.c
@@ -12,28 +12,93 @@
#include "bme680.h"
+struct bme680_spi_bus_context {
+ struct spi_device *spi;
+ u8 current_page;
+};
+
+/*
+ * In SPI mode there are only 7 address bits, a "page" register determines
+ * which part of the 8-bit range is active. This function looks at the address
+ * and writes the page selection bit if needed
+ */
+static int bme680_regmap_spi_select_page(
+ struct bme680_spi_bus_context *ctx, u8 reg)
+{
+ struct spi_device *spi = ctx->spi;
+ int ret;
+ u8 buf[2];
+ u8 page = (reg & 0x80) ? 0 : 1; /* Page "1" is low range */
+
+ if (page == ctx->current_page)
+ return 0;
+
+ /*
+ * Data sheet claims we're only allowed to change bit 4, so we must do
+ * a read-modify-write on each and every page select
+ */
+ buf[0] = BME680_REG_STATUS;
+ ret = spi_write_then_read(spi, buf, 1, buf + 1, 1);
+ if (ret < 0) {
+ dev_err(&spi->dev, "failed to set page %u\n", page);
+ return ret;
+ }
+
+ buf[0] = BME680_REG_STATUS;
+ if (page)
+ buf[1] |= BME680_SPI_MEM_PAGE_BIT;
+ else
+ buf[1] &= ~BME680_SPI_MEM_PAGE_BIT;
+
+ ret = spi_write(spi, buf, 2);
+ if (ret < 0) {
+ dev_err(&spi->dev, "failed to set page %u\n", page);
+ return ret;
+ }
+
+ ctx->current_page = page;
+
+ return 0;
+}
+
static int bme680_regmap_spi_write(void *context, const void *data,
size_t count)
{
- struct spi_device *spi = context;
+ struct bme680_spi_bus_context *ctx = context;
+ struct spi_device *spi = ctx->spi;
+ int ret;
u8 buf[2];
memcpy(buf, data, 2);
+
+ ret = bme680_regmap_spi_select_page(ctx, buf[0]);
+ if (ret)
+ return ret;
+
/*
* 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);
+ return spi_write(spi, buf, 2);
}
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;
+ struct bme680_spi_bus_context *ctx = context;
+ struct spi_device *spi = ctx->spi;
+ int ret;
+ u8 addr = *(const u8 *)reg;
+
+ ret = bme680_regmap_spi_select_page(ctx, addr);
+ if (ret)
+ return ret;
- return spi_write_then_read(spi, reg, reg_size, val, val_size);
+ addr |= 0x80; /* bit7 = RW = '1' */
+
+ return spi_write_then_read(spi, &addr, 1, val, val_size);
}
static struct regmap_bus bme680_regmap_bus = {
@@ -46,8 +111,8 @@ static struct regmap_bus bme680_regmap_bus = {
static int bme680_spi_probe(struct spi_device *spi)
{
const struct spi_device_id *id = spi_get_device_id(spi);
+ struct bme680_spi_bus_context *bus_context;
struct regmap *regmap;
- unsigned int val;
int ret;
spi->bits_per_word = 8;
@@ -57,45 +122,21 @@ static int bme680_spi_probe(struct spi_device *spi)
return ret;
}
+ bus_context = devm_kzalloc(&spi->dev, sizeof(*bus_context), GFP_KERNEL);
+ if (!bus_context)
+ return -ENOMEM;
+
+ bus_context->spi = spi;
+ bus_context->current_page = 0xff; /* Undefined on warm boot */
+
regmap = devm_regmap_init(&spi->dev, &bme680_regmap_bus,
- &spi->dev, &bme680_regmap_config);
+ bus_context, &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);
}