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@@ -0,0 +1,37 @@
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+From bb29785e0d6d150181704be2efcc3141044625e2 Mon Sep 17 00:00:00 2001
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+From: Grant Likely <[email protected]>
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+Date: Fri, 21 Dec 2012 19:32:09 +0000
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+Subject: [PATCH] spi/of: Use DT aliases for assigning bus number
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+
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+Linux assigns a number to each spi_master in the system, but when the
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+platform used the device tree, the numbers are dynamically assigned and
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+are not predictable. In general this shouldn't matter since the kernel
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+doesn't use the bus number for anything other than matching a bus to
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+spi_boardinfo (not used for DT). However, sometimes userspace needs to
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+figure out which bus is which, so it makes sense to use the global
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+/aliases namespace to choose a specific bus number.
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+
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+It is safe to derive the bus number from an alias because aliases will
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+never cause two buses to try and use the same bus number. (At one time
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+the cell-index property was used for this purpose, but cell-index has
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+the risk of an id collision).
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+
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+Signed-off-by: Grant Likely <[email protected]>
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+Cc: Anatolij Gustschin <[email protected]>
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+Cc: Mark Brown <[email protected]>
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+---
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+ drivers/spi/spi.c | 3 +++
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+ 1 file changed, 3 insertions(+)
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+
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+--- a/drivers/spi/spi.c
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++++ b/drivers/spi/spi.c
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+@@ -1135,6 +1135,9 @@ int spi_register_master(struct spi_maste
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+ if (master->num_chipselect == 0)
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+ return -EINVAL;
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+
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++ if ((master->bus_num < 0) && master->dev.of_node)
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++ master->bus_num = of_alias_get_id(master->dev.of_node, "spi");
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++
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+ /* convention: dynamically assigned bus IDs count down from the max */
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+ if (master->bus_num < 0) {
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+ /* FIXME switch to an IDR based scheme, something like
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Gabor Juhos