mtd: m25p80: allow arbitrary OF matching for "jedec,spi-nor" (43163022) · Commits · 戴 / test

When we added the "jedec,spi-nor" compatible string for use in this driver, we added it as a modalias option. The modalias can be derived in different ways for platform devices vs. device tree (of_*) matching. But for device tree matching (the primary target of this identifier string), the modalias is determined from the first entry in the 'compatible' property. IOW, the following properties would bind to this driver: // Option (a), modalias = "spi-nor" compatible = "jedec,spi-nor"; // Option (b), modalias = "spi-nor" compatible = "idontknowwhatimdoing,spi-nor"; But the following would not: // Option (c), modalias = "shinynewdevice" compatible = "myvendor,shinynewdevice", "jedec,spi-nor"; So, we'd like to match (a) and (c) (even when we don't have an explicit entry for "shinynewdevice"), and we'd rather not allow (b). To do this, we (1) always (for devices without specific platform data) pass the modalias to the spi-nor library; (2) rework the spi-nor library to not reject "bad" names, and instead just fall back to autodetection; and (3) add the .of_match_table to properly catch all "jedec,spi-nor". This allows (a) and (c) without warnings, and rejects (b). Signed-off-by:

Brian Norris <computersforpeace@gmail.com>

drivers/mtd/devices/m25p80.c

+11 −7

Original line number	Diff line number	Diff line
		@@ -223,8 +223,6 @@ static int m25p_probe(struct spi_device *spi)
		*/
		if (data && data->type)
		flash_name = data->type;
		else if (!strcmp(spi->modalias, "spi-nor"))
		flash_name = NULL; /* auto-detect */
		else
		flash_name = spi->modalias;

		@@ -289,19 +287,25 @@ static const struct spi_device_id m25p_ids[] = {
		{"m25p40-nonjedec"}, {"m25p80-nonjedec"}, {"m25p16-nonjedec"},
		{"m25p32-nonjedec"}, {"m25p64-nonjedec"}, {"m25p128-nonjedec"},

		/*
		* Generic support for SPI NOR that can be identified by the JEDEC READ
		* ID opcode (0x9F). Use this, if possible.
		*/
		{"spi-nor"},
		{ },
		};
		MODULE_DEVICE_TABLE(spi, m25p_ids);

		static const struct of_device_id m25p_of_table[] = {
		/*
		* Generic compatibility for SPI NOR that can be identified by the
		* JEDEC READ ID opcode (0x9F). Use this, if possible.
		*/
		{ .compatible = "jedec,spi-nor" },
		{}
		};
		MODULE_DEVICE_TABLE(of, m25p_of_table);

		static struct spi_driver m25p80_driver = {
		.driver = {
		.name = "m25p80",
		.owner = THIS_MODULE,
		.of_match_table = m25p_of_table,
		},
		.id_table = m25p_ids,
		.probe = m25p_probe,

drivers/mtd/spi-nor/spi-nor.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -1015,11 +1015,11 @@ int spi_nor_scan(struct spi_nor nor, const char name, enum read_mode mode)
		if (ret)
		return ret;

		/* Try to auto-detect if chip name wasn't specified */
		if (!name)
		id = spi_nor_read_id(nor);
		else
		if (name)
		id = spi_nor_match_id(name);
		/* Try to auto-detect if chip name wasn't specified or not found */
		if (!id)
		id = spi_nor_read_id(nor);
		if (IS_ERR_OR_NULL(id))
		return -ENOENT;

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