37 lines
1 KiB
Diff
37 lines
1 KiB
Diff
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From: Felix Fietkau <nbd@nbd.name>
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Date: Fri, 23 Feb 2018 17:12:16 +0100
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Subject: [PATCH] mtd: m25p80: allow fallback from spi_flash_read to regular
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SPI transfer
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Some flash controllers, e.g. on the ath79 platform can support a fast
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flash read via memory mapping, but only if the flash chip is in
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3-byte address mode.
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Since spi_flash_read_supported does not have access to the same data as
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spi_flash_read, the driver can't detect an unsupported call until m25p80
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has decided to use spi_flash_read.
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Allow the driver to indicate a fallback to a regular SPI transfer by
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returning -EOPNOTSUPP
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Signed-off-by: Felix Fietkau <nbd@nbd.name>
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---
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--- a/drivers/mtd/devices/m25p80.c
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+++ b/drivers/mtd/devices/m25p80.c
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@@ -155,9 +155,11 @@ static ssize_t m25p80_read(struct spi_no
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msg.data_nbits = m25p80_rx_nbits(nor);
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ret = spi_flash_read(spi, &msg);
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- if (ret < 0)
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- return ret;
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- return msg.retlen;
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+ if (ret != -EOPNOTSUPP) {
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+ if (ret < 0)
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+ return ret;
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+ return msg.retlen;
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+ }
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}
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spi_message_init(&m);
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