s32 t_fine;
};
+static const struct regmap_range bme680_volatile_ranges[] = {
+ regmap_reg_range(BME680_REG_MEAS_STAT_0, BME680_REG_GAS_R_LSB),
+ regmap_reg_range(BME680_REG_STATUS, BME680_REG_STATUS),
+ regmap_reg_range(BME680_T2_LSB_REG, BME680_GH3_REG),
+};
+
+static const struct regmap_access_table bme680_volatile_table = {
+ .yes_ranges = bme680_volatile_ranges,
+ .n_yes_ranges = ARRAY_SIZE(bme680_volatile_ranges),
+};
+
const struct regmap_config bme680_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
+ .max_register = 0xef,
+ .volatile_table = &bme680_volatile_table,
+ .cache_type = REGCACHE_RBTREE,
};
EXPORT_SYMBOL(bme680_regmap_config);
s64 var1, var2, var3;
s16 calc_temp;
+ /* If the calibration is invalid, attempt to reload it */
+ if (!calib->par_t2)
+ bme680_read_calib(data, calib);
+
var1 = (adc_temp >> 3) - (calib->par_t1 << 1);
var2 = (var1 * calib->par_t2) >> 11;
var3 = ((var1 >> 1) * (var1 >> 1)) >> 12;
{
struct iio_dev *indio_dev;
struct bme680_data *data;
+ unsigned int val;
int ret;
+ ret = regmap_write(regmap, BME680_REG_SOFT_RESET,
+ BME680_CMD_SOFTRESET);
+ if (ret < 0) {
+ dev_err(dev, "Failed to reset chip\n");
+ return ret;
+ }
+
+ ret = regmap_read(regmap, BME680_REG_CHIP_ID, &val);
+ if (ret < 0) {
+ dev_err(dev, "Error reading chip ID\n");
+ return ret;
+ }
+
+ if (val != BME680_CHIP_ID_VAL) {
+ dev_err(dev, "Wrong chip ID, got %x expected %x\n",
+ val, BME680_CHIP_ID_VAL);
+ return -ENODEV;
+ }
+
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
#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 = {
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;
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);
}
projects / linux.git / commitdiff