2018-08-17 10:08:48

by Chuanhua Han

Subject: [PATCH] spi: fsl-espi: master->mem_ops is implemented in the controller

The length of the transmitted data needs to be adjusted due to the maximum
length limit for espi transmission messages

Signed-off-by: Chuanhua Han <[email protected]>
---
drivers/spi/spi-fsl-espi.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
index 1d332e2..4724127 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/drivers/spi/spi-fsl-espi.c
@@ -22,6 +22,7 @@
#include <linux/spi/spi.h>
#include <linux/pm_runtime.h>
#include <sysdev/fsl_soc.h>
+#include <linux/spi/spi-mem.h>

/* eSPI Controller registers */
#define ESPI_SPMODE 0x00 /* eSPI mode register */
@@ -659,6 +660,29 @@ static void fsl_espi_init_regs(struct device *dev, bool initial)
fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE);
}

+static int fsl_espi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
+{
+ if (!mem || !op)
+ return -EINVAL;
+ op->data.nbytes = min3((unsigned long)op->data.nbytes,
+ spi_max_transfer_size(mem->spi),
+ spi_max_message_size(mem->spi) -
+ sizeof(op->cmd.opcode) -
+ op->addr.nbytes -
+ op->dummy.nbytes);
+ return 0;
+}
+
+static int fsl_espi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
+{
+ return -ENOTSUPP;
+}
+
+static const struct spi_controller_mem_ops fsl_espi_mem_ops = {
+ .adjust_op_size = fsl_espi_adjust_op_size,
+ .exec_op = fsl_espi_exec_op,
+};
+
static int fsl_espi_probe(struct device *dev, struct resource *mem,
unsigned int irq, unsigned int num_cs)
{
@@ -682,6 +706,7 @@ static int fsl_espi_probe(struct device *dev, struct resource *mem,
master->auto_runtime_pm = true;
master->max_message_size = fsl_espi_max_message_size;
master->num_chipselect = num_cs;
+ master->mem_ops = &fsl_espi_mem_ops;

espi = spi_master_get_devdata(master);
spin_lock_init(&espi->lock);
--
2.7.4

2018-08-17 10:34:18

by Boris Brezillon

Subject: Re: [PATCH] spi: fsl-espi: master->mem_ops is implemented in the controller

On Fri, 17 Aug 2018 18:07:05 +0800
Chuanhua Han <[email protected]> wrote:

> The length of the transmitted data needs to be adjusted due to the maximum
> length limit for espi transmission messages
>
> Signed-off-by: Chuanhua Han <[email protected]>
> ---
> drivers/spi/spi-fsl-espi.c | 25 +++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
> index 1d332e2..4724127 100644
> --- a/drivers/spi/spi-fsl-espi.c
> +++ b/drivers/spi/spi-fsl-espi.c
> @@ -22,6 +22,7 @@
> #include <linux/spi/spi.h>
> #include <linux/pm_runtime.h>
> #include <sysdev/fsl_soc.h>
> +#include <linux/spi/spi-mem.h>
>
> /* eSPI Controller registers */
> #define ESPI_SPMODE 0x00 /* eSPI mode register */
> @@ -659,6 +660,29 @@ static void fsl_espi_init_regs(struct device *dev, bool initial)
> fsl_espi_write_reg(espi, ESPI_SPMODE, SPMODE_INIT_VAL | SPMODE_ENABLE);
> }
>
> +static int fsl_espi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
> +{
> + if (!mem || !op)
> + return -EINVAL;
> + op->data.nbytes = min3((unsigned long)op->data.nbytes,
> + spi_max_transfer_size(mem->spi),
> + spi_max_message_size(mem->spi) -
> + sizeof(op->cmd.opcode) -
> + op->addr.nbytes -
> + op->dummy.nbytes);

Oops! Looks like I was wrong in my initial review, this code is generic
and should be placed in spi_mem_adjust_op_size() if !ctlr->mem_ops
or !ctlr->mem_ops->exec_op:

int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
{
struct spi_controller *ctlr = mem->spi->controller;

if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size)
return ctlr->mem_ops->adjust_op_size(mem, op);

if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op)
op->data.nbytes = min3((unsigned long)op->data.nbytes,
spi_max_transfer_size(mem->spi),
spi_max_message_size(mem->spi) -
sizeof(op->cmd.opcode) -
op->addr.nbytes -
op->dummy.nbytes);

return 0;
}

Also, you don't seem to check spi_max_message_size(mem->spi) value
before subtracting opcode, addr and dummy bytes.


> + return 0;
> +}
> +
> +static int fsl_espi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static const struct spi_controller_mem_ops fsl_espi_mem_ops = {
> + .adjust_op_size = fsl_espi_adjust_op_size,
> + .exec_op = fsl_espi_exec_op,
> +};
> +
> static int fsl_espi_probe(struct device *dev, struct resource *mem,
> unsigned int irq, unsigned int num_cs)
> {
> @@ -682,6 +706,7 @@ static int fsl_espi_probe(struct device *dev, struct resource *mem,
> master->auto_runtime_pm = true;
> master->max_message_size = fsl_espi_max_message_size;
> master->num_chipselect = num_cs;
> + master->mem_ops = &fsl_espi_mem_ops;
>
> espi = spi_master_get_devdata(master);
> spin_lock_init(&espi->lock);