Re: [PATCH] mtd: m25p80: Modify the name of mtd_info
From: Brian Norris <computersforpeace@gmail.com>
Date: 2014-04-16 06:48:06
On Fri, Mar 21, 2014 at 07:16:18PM +0800, Hou Zhiqiang wrote:
quoted hunk ↗ jump to hunk
To specify spi flash layouts by "mtdparts=..." in cmdline, we must give mtd_info a fixed name,because the cmdlinepart's parser will match the name of mtd_info given in cmdline. Now, if use DT, the mtd_info's name will be spi->dev->name. It consists of spi_master->bus_num, and the spi_master->bus_num maybe dynamically fetched. So, in this case, replace the component bus_num with thei physical address of spi master. Signed-off-by: Hou Zhiqiang <redacted> --- drivers/mtd/devices/m25p80.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index 7eda71d..64450a2 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c@@ -30,6 +30,7 @@ #include <linux/mtd/cfi.h> #include <linux/mtd/mtd.h> #include <linux/mtd/partitions.h> +#include <linux/of_address.h> #include <linux/of_platform.h> #include <linux/spi/spi.h>@@ -934,9 +935,11 @@ static int m25p_probe(struct spi_device *spi) struct flash_platform_data *data; struct m25p *flash; struct flash_info *info; - unsigned i; + unsigned i, ret; struct mtd_part_parser_data ppdata; struct device_node *np = spi->dev.of_node; + struct resource res; + struct device_node *mnp = spi->master->dev.of_node; /* Platform data helps sort out which chip type we have, as * well as how this board partitions it. If we don't have@@ -1009,8 +1012,17 @@ static int m25p_probe(struct spi_device *spi) if (data && data->name) flash->mtd.name = data->name; - else - flash->mtd.name = dev_name(&spi->dev); + else{ + ret = of_address_to_resource(mnp, 0, &res);
You're making a lot assumptions about the SPI master/device relationship -- that the master has a device-node; that the first resource of the master is its physical address (this is not guaranteed by DT semantics). Please do not do this.
+ if (ret) {
+ dev_err(&spi->dev, "failed to get spi master resource\n");
+ return ret;This is wrong. It breaks all !CONFIG_OF cases which didn't specify a name via platform data.
+ } + flash->mtd.name = kasprintf(GFP_KERNEL, "spi%x.%d", + (unsigned)res.start, spi->chip_select); + if (!flash->mtd.name) + return -ENOMEM; + } flash->mtd.type = MTD_NORFLASH; flash->mtd.writesize = 1;
Brian