We now have separate functions for registering and unregistering
individual flash chips, instead of the entire controller. This is a
preparatory step for allowing userspace to request that a specific
chip be attached or detached at runtime.
Signed-off-by: Zev Weiss <[email protected]>
---
drivers/mtd/spi-nor/controllers/aspeed-smc.c | 73 ++++++++++++--------
1 file changed, 45 insertions(+), 28 deletions(-)
diff --git a/drivers/mtd/spi-nor/controllers/aspeed-smc.c b/drivers/mtd/spi-nor/controllers/aspeed-smc.c
index 7225870e8b18..3c153104a905 100644
--- a/drivers/mtd/spi-nor/controllers/aspeed-smc.c
+++ b/drivers/mtd/spi-nor/controllers/aspeed-smc.c
@@ -107,9 +107,10 @@ struct aspeed_smc_controller {
const struct aspeed_smc_info *info; /* type info of controller */
void __iomem *regs; /* controller registers */
void __iomem *ahb_base; /* per-chip windows resource */
+ struct resource *ahb_res; /* resource for AHB address space */
u32 ahb_window_size; /* full mapping window size */
- struct aspeed_smc_chip *chips[]; /* pointers to attached chips */
+ struct aspeed_smc_chip *chips[]; /* pointers to connected chips */
};
/*
@@ -399,15 +400,24 @@ static ssize_t aspeed_smc_write_user(struct spi_nor *nor, loff_t to,
return len;
}
+static int aspeed_smc_unregister_chip(struct aspeed_smc_chip *chip)
+{
+ return mtd_device_unregister(&chip->nor.mtd);
+}
+
static int aspeed_smc_unregister(struct aspeed_smc_controller *controller)
{
struct aspeed_smc_chip *chip;
- int n;
+ int n, ret;
for (n = 0; n < controller->info->nce; n++) {
chip = controller->chips[n];
- if (chip)
- mtd_device_unregister(&chip->nor.mtd);
+ if (chip) {
+ ret = aspeed_smc_unregister_chip(chip);
+ if (ret)
+ dev_warn(controller->dev, "failed to unregister CS%d: %d\n",
+ n, ret);
+ }
}
return 0;
@@ -756,14 +766,39 @@ static const struct spi_nor_controller_ops aspeed_smc_controller_ops = {
.write = aspeed_smc_write_user,
};
-static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
- struct device_node *np, struct resource *r)
+static int aspeed_smc_register_chip(struct aspeed_smc_chip *chip)
{
- const struct spi_nor_hwcaps hwcaps = {
+ static const struct spi_nor_hwcaps hwcaps = {
.mask = SNOR_HWCAPS_READ |
SNOR_HWCAPS_READ_FAST |
SNOR_HWCAPS_PP,
};
+ int ret;
+
+ ret = aspeed_smc_chip_setup_init(chip, chip->controller->ahb_res);
+ if (ret)
+ goto out;
+
+ /*
+ * TODO: Add support for Dual and Quad SPI protocols attach when board
+ * support is present as determined by of property.
+ */
+ ret = spi_nor_scan(&chip->nor, NULL, &hwcaps);
+ if (ret)
+ goto out;
+
+ ret = aspeed_smc_chip_setup_finish(chip);
+ if (ret)
+ goto out;
+
+ ret = mtd_device_register(&chip->nor.mtd, NULL, 0);
+out:
+ return ret;
+}
+
+static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
+ struct device_node *np, struct resource *r)
+{
const struct aspeed_smc_info *info = controller->info;
struct device *dev = controller->dev;
struct device_node *child;
@@ -773,7 +808,6 @@ static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
for_each_available_child_of_node(np, child) {
struct aspeed_smc_chip *chip;
struct spi_nor *nor;
- struct mtd_info *mtd;
/* This driver does not support NAND or NOR flash devices. */
if (!of_device_is_compatible(child, "jedec,spi-nor"))
@@ -810,35 +844,17 @@ static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
chip->cs = cs;
nor = &chip->nor;
- mtd = &nor->mtd;
nor->dev = dev;
nor->priv = chip;
spi_nor_set_flash_node(nor, child);
nor->controller_ops = &aspeed_smc_controller_ops;
- ret = aspeed_smc_chip_setup_init(chip, r);
- if (ret)
- break;
-
- /*
- * TODO: Add support for Dual and Quad SPI protocols
- * attach when board support is present as determined
- * by of property.
- */
- ret = spi_nor_scan(nor, NULL, &hwcaps);
- if (ret)
- break;
-
- ret = aspeed_smc_chip_setup_finish(chip);
- if (ret)
- break;
+ controller->chips[cs] = chip;
- ret = mtd_device_register(mtd, NULL, 0);
+ ret = aspeed_smc_register_chip(chip);
if (ret)
break;
-
- controller->chips[cs] = chip;
}
if (ret) {
@@ -881,6 +897,7 @@ static int aspeed_smc_probe(struct platform_device *pdev)
return PTR_ERR(controller->regs);
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ controller->ahb_res = res;
controller->ahb_base = devm_ioremap_resource(dev, res);
if (IS_ERR(controller->ahb_base))
return PTR_ERR(controller->ahb_base);
--
2.33.0
On Wed, 29 Sep 2021, Zev Weiss wrote:
> We now have separate functions for registering and unregistering
> individual flash chips, instead of the entire controller. This is a
> preparatory step for allowing userspace to request that a specific
> chip be attached or detached at runtime.
>
> Signed-off-by: Zev Weiss <[email protected]>
> ---
> drivers/mtd/spi-nor/controllers/aspeed-smc.c | 73 ++++++++++++--------
> 1 file changed, 45 insertions(+), 28 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/controllers/aspeed-smc.c b/drivers/mtd/spi-nor/controllers/aspeed-smc.c
> index 7225870e8b18..3c153104a905 100644
> --- a/drivers/mtd/spi-nor/controllers/aspeed-smc.c
> +++ b/drivers/mtd/spi-nor/controllers/aspeed-smc.c
> @@ -107,9 +107,10 @@ struct aspeed_smc_controller {
> const struct aspeed_smc_info *info; /* type info of controller */
> void __iomem *regs; /* controller registers */
> void __iomem *ahb_base; /* per-chip windows resource */
> + struct resource *ahb_res; /* resource for AHB address space */
> u32 ahb_window_size; /* full mapping window size */
>
> - struct aspeed_smc_chip *chips[]; /* pointers to attached chips */
> + struct aspeed_smc_chip *chips[]; /* pointers to connected chips */
> };
>
> /*
> @@ -399,15 +400,24 @@ static ssize_t aspeed_smc_write_user(struct spi_nor *nor, loff_t to,
> return len;
> }
>
> +static int aspeed_smc_unregister_chip(struct aspeed_smc_chip *chip)
> +{
> + return mtd_device_unregister(&chip->nor.mtd);
> +}
> +
> static int aspeed_smc_unregister(struct aspeed_smc_controller *controller)
> {
> struct aspeed_smc_chip *chip;
> - int n;
> + int n, ret;
>
> for (n = 0; n < controller->info->nce; n++) {
> chip = controller->chips[n];
> - if (chip)
> - mtd_device_unregister(&chip->nor.mtd);
> + if (chip) {
> + ret = aspeed_smc_unregister_chip(chip);
> + if (ret)
> + dev_warn(controller->dev, "failed to unregister CS%d: %d\n",
> + n, ret);
> + }
> }
>
> return 0;
> @@ -756,14 +766,39 @@ static const struct spi_nor_controller_ops aspeed_smc_controller_ops = {
> .write = aspeed_smc_write_user,
> };
>
> -static int aspeed_smc_setup_flash(struct aspeed_smc_controller *controller,
> - struct device_node *np, struct resource *r)
> +static int aspeed_smc_register_chip(struct aspeed_smc_chip *chip)
> {
> - const struct spi_nor_hwcaps hwcaps = {
> + static const struct spi_nor_hwcaps hwcaps = {
> .mask = SNOR_HWCAPS_READ |
> SNOR_HWCAPS_READ_FAST |
> SNOR_HWCAPS_PP,
> };
> + int ret;
> +
> + ret = aspeed_smc_chip_setup_init(chip, chip->controller->ahb_res);
> + if (ret)
> + goto out;
> +
> + /*
> + * TODO: Add support for Dual and Quad SPI protocols attach when board
> + * support is present as determined by of property.
> + */
> + ret = spi_nor_scan(&chip->nor, NULL, &hwcaps);
> + if (ret)
> + goto out;
> +
> + ret = aspeed_smc_chip_setup_finish(chip);
> + if (ret)
> + goto out;
> +
> + ret = mtd_device_register(&chip->nor.mtd, NULL, 0);
> +out:
> + return ret;
> +}
I was looking into this driver probe walking sub-nodes.
It looks like all controller drivers are doing / have to do similar work -
(1) Parse common dt bindings documented in Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml
(2) Run spi_nor_scan() with tweaked/reduced capabilities.
(3) mtd_register_device().
It would be good to absorb this workflow in mtd/spi-nor core and add 'reserved' as common
dt property to avoid (2) and (3) from probe.
Regards,
Dhananjay