Re: [PATCH v2 2/9] mfd: cs5535-mfd: Remove mfd_cell->id hack

From: Daniel Thompson
Date: Mon Oct 21 2019 - 07:11:45 EST


On Mon, Oct 21, 2019 at 11:58:15AM +0100, Lee Jones wrote:
> The current implementation abuses the platform 'id' mfd_cell member
> to index into the correct resources entry. If we place all cells
> into their numbered slots, we can cycle through all the cell entries
> and only process the populated ones which avoids this behaviour.
>
> Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
> ---
> drivers/mfd/cs5535-mfd.c | 31 +++++++++++++------------------
> 1 file changed, 13 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/mfd/cs5535-mfd.c b/drivers/mfd/cs5535-mfd.c
> index 2c47afc22d24..9ce6bbcdbda1 100644
> --- a/drivers/mfd/cs5535-mfd.c
> +++ b/drivers/mfd/cs5535-mfd.c
> @@ -62,26 +62,22 @@ static int cs5535_mfd_res_disable(struct platform_device *pdev)
> static struct resource cs5535_mfd_resources[NR_BARS];
>
> static struct mfd_cell cs5535_mfd_cells[] = {

This array is sized from the initializer...

> - {
> - .id = SMB_BAR,
> + [SMB_BAR] = {
> .name = "cs5535-smb",
> .num_resources = 1,
> .resources = &cs5535_mfd_resources[SMB_BAR],
> },
> - {
> - .id = GPIO_BAR,
> + [GPIO_BAR] = {
> .name = "cs5535-gpio",
> .num_resources = 1,
> .resources = &cs5535_mfd_resources[GPIO_BAR],
> },
> - {
> - .id = MFGPT_BAR,
> + [MFGPT_BAR] = {
> .name = "cs5535-mfgpt",
> .num_resources = 1,
> .resources = &cs5535_mfd_resources[MFGPT_BAR],
> },
> - {
> - .id = PMS_BAR,
> + [PMS_BAR] = {
> .name = "cs5535-pms",
> .num_resources = 1,
> .resources = &cs5535_mfd_resources[PMS_BAR],
> @@ -89,8 +85,7 @@ static struct mfd_cell cs5535_mfd_cells[] = {
> .enable = cs5535_mfd_res_enable,
> .disable = cs5535_mfd_res_disable,
> },
> - {
> - .id = ACPI_BAR,
> + [ACPI_BAR] = {
> .name = "cs5535-acpi",
> .num_resources = 1,
> .resources = &cs5535_mfd_resources[ACPI_BAR],
> @@ -115,16 +110,16 @@ static int cs5535_mfd_probe(struct pci_dev *pdev,
> return err;
>
> /* fill in IO range for each cell; subdrivers handle the region */
> - for (i = 0; i < ARRAY_SIZE(cs5535_mfd_cells); i++) {
> - int bar = cs5535_mfd_cells[i].id;
> - struct resource *r = &cs5535_mfd_resources[bar];
> + for (i = 0; i < NR_BARS; i++) {

... which means this translation from ARRAY_SIZE() to NR_BARS
is rather odd.

I don't care whether the array is sized using NR_BARS or the loop
uses ARRAY_SIZE() but IMHO the loop boundary condition must match
the array declaration.

With that fixed free to throw the following onto the next rev:
Reviewed-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>


Daniel.