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Diffstat (limited to 'include/linux/spi/mcp23s08.h')
-rw-r--r--include/linux/spi/mcp23s08.h25
1 files changed, 16 insertions, 9 deletions
diff --git a/include/linux/spi/mcp23s08.h b/include/linux/spi/mcp23s08.h
index 835ddf47d45c..22ef107d7704 100644
--- a/include/linux/spi/mcp23s08.h
+++ b/include/linux/spi/mcp23s08.h
@@ -1,18 +1,25 @@
-/* FIXME driver should be able to handle all four slaves that
- * can be hooked up to each chipselect, as well as IRQs...
- */
+/* FIXME driver should be able to handle IRQs... */
+
+struct mcp23s08_chip_info {
+ bool is_present; /* true iff populated */
+ u8 pullups; /* BIT(x) means enable pullup x */
+};
struct mcp23s08_platform_data {
- /* four slaves can share one SPI chipselect */
- u8 slave;
+ /* Four slaves (numbered 0..3) can share one SPI chipselect, and
+ * will provide 8..32 GPIOs using 1..4 gpio_chip instances.
+ */
+ struct mcp23s08_chip_info chip[4];
- /* number assigned to the first GPIO */
+ /* "base" is the number of the first GPIO. Dynamic assignment is
+ * not currently supported, and even if there are gaps in chip
+ * addressing the GPIO numbers are sequential .. so for example
+ * if only slaves 0 and 3 are present, their GPIOs range from
+ * base to base+15.
+ */
unsigned base;
- /* pins with pullups */
- u8 pullups;
-
void *context; /* param to setup/teardown */
int (*setup)(struct spi_device *spi,
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