| Message ID | 20180410224439.9260-8-boris.brezillon@bootlin.com |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | spi: Extend the framework to generically support memory devices | expand |
On Wed, 11 Apr 2018 00:44:36 +0200 Boris Brezillon <boris.brezillon@bootlin.com> wrote: > The spi_mem interface is meant to replace the spi_flash_read() one. > Implement the ->exec_op() method so that we can smoothly get rid of the > old interface. > > Note that the current ->flash_read() implementation looks a bit fragile > since it does not take the ->read_opcode passed by the spi-nor layer > into account, which means if might not work with all kind of NORs. > > Anyway, I left the logic unchanged and added a few extra checks to make > sure we're receiving something that looks like a NOR read operation. > > Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> > --- > Changes in v2: > - include spi-mem.h > - treat op->addr.val differently since it's now an u64 > --- > drivers/spi/spi-bcm2835.c | 1 + > drivers/spi/spi-bcm53xx.c | 36 +++++++++++++++++++++++++++++++++++- > 2 files changed, 36 insertions(+), 1 deletion(-) > > diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c > index f35cc10772f6..41ed371eaf15 100644 > --- a/drivers/spi/spi-bcm2835.c > +++ b/drivers/spi/spi-bcm2835.c > @@ -37,6 +37,7 @@ > #include <linux/of_gpio.h> > #include <linux/of_irq.h> > #include <linux/spi/spi.h> > +#include <linux/spi/spi-mem.h> Oops, I didn't modify the appropriate file. This line should be added in drivers/spi/spi-bcm53xx.c. I'll fix that in the next version. > > /* SPI register offsets */ > #define BCM2835_SPI_CS 0x00 > diff --git a/drivers/spi/spi-bcm53xx.c b/drivers/spi/spi-bcm53xx.c > index d02ceb7a29d1..016059d3160b 100644 > --- a/drivers/spi/spi-bcm53xx.c > +++ b/drivers/spi/spi-bcm53xx.c > @@ -257,6 +257,38 @@ static int bcm53xxspi_transfer_one(struct spi_master *master, > return 0; > } > > +static int bcm53xxspi_exec_mem_op(struct spi_mem *mem, > + const struct spi_mem_op *op) > +{ > + struct bcm53xxspi *b53spi = spi_master_get_devdata(mem->spi->master); > + u32 from; > + > + /* > + * FIXME: There's nothing in this driver programming the opcode and > + * buswidth to be used when a read is done on the mmio window, but it > + * seems to be used to access a SPI NOR device, so restrict access > + * access to SPINOR_OP_READ commands. > + */ > + if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN || > + op->addr.nbytes != 3 || op->cmd.opcode != 0x3) > + return -ENOTSUPP; > + > + /* Return -ENOTSUPP so that the core can fall back to normal reads. */ > + from = op->addr.val; > + if (from + op->data.nbytes > BCM53XXSPI_FLASH_WINDOW) > + return -ENOTSUPP; > + > + bcm53xxspi_enable_bspi(b53spi); > + memcpy_fromio(op->data.buf.in, b53spi->mmio_base + from, > + op->data.nbytes); > + > + return 0; > +} > + > +static const struct spi_controller_mem_ops bcm53xxspi_mem_ops = { > + .exec_op = bcm53xxspi_exec_mem_op, > +}; > + > static int bcm53xxspi_flash_read(struct spi_device *spi, > struct spi_flash_read_message *msg) > { > @@ -311,8 +343,10 @@ static int bcm53xxspi_bcma_probe(struct bcma_device *core) > > master->dev.of_node = dev->of_node; > master->transfer_one = bcm53xxspi_transfer_one; > - if (b53spi->mmio_base) > + if (b53spi->mmio_base) { > + master->mem_ops = &bcm53xxspi_mem_ops; > master->spi_flash_read = bcm53xxspi_flash_read; > + } > > bcma_set_drvdata(core, b53spi); >
On 11 April 2018 at 00:44, Boris Brezillon <boris.brezillon@bootlin.com> wrote: > The spi_mem interface is meant to replace the spi_flash_read() one. > Implement the ->exec_op() method so that we can smoothly get rid of the > old interface. > > Note that the current ->flash_read() implementation looks a bit fragile > since it does not take the ->read_opcode passed by the spi-nor layer > into account, which means if might not work with all kind of NORs. > > Anyway, I left the logic unchanged and added a few extra checks to make > sure we're receiving something that looks like a NOR read operation. > > Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Actually, I've just sent [PATCH] spi: remove the older/duplicated bcm53xx driver https://patchwork.kernel.org/patch/10383719/ This patch can be probably dropped, as I expect spi-bcm53xx.c to disappear soon.
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index f35cc10772f6..41ed371eaf15 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -37,6 +37,7 @@ #include <linux/of_gpio.h> #include <linux/of_irq.h> #include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> /* SPI register offsets */ #define BCM2835_SPI_CS 0x00 diff --git a/drivers/spi/spi-bcm53xx.c b/drivers/spi/spi-bcm53xx.c index d02ceb7a29d1..016059d3160b 100644 --- a/drivers/spi/spi-bcm53xx.c +++ b/drivers/spi/spi-bcm53xx.c @@ -257,6 +257,38 @@ static int bcm53xxspi_transfer_one(struct spi_master *master, return 0; } +static int bcm53xxspi_exec_mem_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + struct bcm53xxspi *b53spi = spi_master_get_devdata(mem->spi->master); + u32 from; + + /* + * FIXME: There's nothing in this driver programming the opcode and + * buswidth to be used when a read is done on the mmio window, but it + * seems to be used to access a SPI NOR device, so restrict access + * access to SPINOR_OP_READ commands. + */ + if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN || + op->addr.nbytes != 3 || op->cmd.opcode != 0x3) + return -ENOTSUPP; + + /* Return -ENOTSUPP so that the core can fall back to normal reads. */ + from = op->addr.val; + if (from + op->data.nbytes > BCM53XXSPI_FLASH_WINDOW) + return -ENOTSUPP; + + bcm53xxspi_enable_bspi(b53spi); + memcpy_fromio(op->data.buf.in, b53spi->mmio_base + from, + op->data.nbytes); + + return 0; +} + +static const struct spi_controller_mem_ops bcm53xxspi_mem_ops = { + .exec_op = bcm53xxspi_exec_mem_op, +}; + static int bcm53xxspi_flash_read(struct spi_device *spi, struct spi_flash_read_message *msg) { @@ -311,8 +343,10 @@ static int bcm53xxspi_bcma_probe(struct bcma_device *core) master->dev.of_node = dev->of_node; master->transfer_one = bcm53xxspi_transfer_one; - if (b53spi->mmio_base) + if (b53spi->mmio_base) { + master->mem_ops = &bcm53xxspi_mem_ops; master->spi_flash_read = bcm53xxspi_flash_read; + } bcma_set_drvdata(core, b53spi);
The spi_mem interface is meant to replace the spi_flash_read() one. Implement the ->exec_op() method so that we can smoothly get rid of the old interface. Note that the current ->flash_read() implementation looks a bit fragile since it does not take the ->read_opcode passed by the spi-nor layer into account, which means if might not work with all kind of NORs. Anyway, I left the logic unchanged and added a few extra checks to make sure we're receiving something that looks like a NOR read operation. Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> --- Changes in v2: - include spi-mem.h - treat op->addr.val differently since it's now an u64 --- drivers/spi/spi-bcm2835.c | 1 + drivers/spi/spi-bcm53xx.c | 36 +++++++++++++++++++++++++++++++++++- 2 files changed, 36 insertions(+), 1 deletion(-)