Re: [PATCH v1 4/5] mfd: lpc_sch: Add support for Intel Quark X1000

Lee Jones
2014-09-01T09:22:15Z

On Fri, 22 Aug 2014, Andy Shevchenko wrote:

> Intel Quark X1000 SoC supports IRQ based GPIO. This patch will
> enable MFD support for Quark X1000 and provide IRQ resources
> to Quark X1000 GPIO device driver.
>
> Signed-off-by: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com>
> Tested-by: Chang Rebecca Swee Fun <rebecca.swee.fun.chang@intel.com>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> drivers/mfd/lpc_sch.c | 41 +++++++++++++++++++++++++++++++++++------
> 1 file changed, 35 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mfd/lpc_sch.c b/drivers/mfd/lpc_sch.c
> index c4eb359..6145a4c 100644
> --- a/drivers/mfd/lpc_sch.c
> +++ b/drivers/mfd/lpc_sch.c
> @@ -37,6 +37,9 @@
> #define GPIO_IO_SIZE 64
> #define GPIO_IO_SIZE_CENTERTON 128
>
> +/* Intel Quark X1000 GPIO IRQ Number */
> +#define GPIO_IRQ_QUARK_X1000 9
> +
> #define WDTBASE 0x84
> #define WDT_IO_SIZE 64
>
> @@ -44,28 +47,37 @@ enum sch_chipsets {
> LPC_SCH = 0, /* Intel Poulsbo SCH */
> LPC_ITC, /* Intel Tunnel Creek */
> LPC_CENTERTON, /* Intel Centerton */
> + LPC_QUARK_X1000, /* Intel Quark X1000 */
> };
>
> struct lpc_sch_info {
> unsigned int io_size_smbus;
> unsigned int io_size_gpio;
> unsigned int io_size_wdt;
> + int irq_gpio;
> };
>
> static struct lpc_sch_info sch_chipset_info[] = {
> [LPC_SCH] = {
> .io_size_smbus = SMBUS_IO_SIZE,
> .io_size_gpio = GPIO_IO_SIZE,
> + .irq_gpio = -1,
> },
> [LPC_ITC] = {
> .io_size_smbus = SMBUS_IO_SIZE,
> .io_size_gpio = GPIO_IO_SIZE,
> .io_size_wdt = WDT_IO_SIZE,
> + .irq_gpio = -1,
> },
> [LPC_CENTERTON] = {
> .io_size_smbus = SMBUS_IO_SIZE,
> .io_size_gpio = GPIO_IO_SIZE_CENTERTON,
> .io_size_wdt = WDT_IO_SIZE,
> + .irq_gpio = -1,
> + },
> + [LPC_QUARK_X1000] = {
> + .io_size_gpio = GPIO_IO_SIZE,
> + .irq_gpio = GPIO_IRQ_QUARK_X1000,
> },
> };
>
> @@ -73,6 +85,7 @@ static const struct pci_device_id lpc_sch_ids[] = {
> { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC), LPC_SCH },
> { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC), LPC_ITC },
> { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB), LPC_CENTERTON },
> + { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB), LPC_QUARK_X1000 },
> { 0, }
> };
> MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
> @@ -106,14 +119,26 @@ static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
> return 0;
> }
>
> +static int lpc_sch_get_irq(struct resource *res, int irq)
> +{
> + if (irq < 0)
> + return -EINVAL;
> +
> + res->start = irq;
> + res->end = irq;
> + res->flags = IORESOURCE_IRQ;
> +
> + return 0;
> +}

Why does this need to be a separate function?

I fear that the code will become unnecessarily fragmented, just for the
sake of it.

> static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
> - const char *name, int size, int id,
> - struct mfd_cell *cell)
> + const char *name, int size, int irq,
> + int id, struct mfd_cell *cell)
> {
> struct resource *res;
> int ret;
>
> - res = devm_kzalloc(&pdev->dev, sizeof(*res), GFP_KERNEL);
> + res = devm_kcalloc(&pdev->dev, 2, sizeof(*res), GFP_KERNEL);
> if (!res)
> return -ENOMEM;
>
> @@ -129,6 +154,10 @@ static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
> cell->ignore_resource_conflicts = true;
> cell->id = id;
>
> + ret = lpc_sch_get_irq(++res, irq);
> + if (!ret)
> + cell->num_resources++;

Once again, you're masking errors. If it's not an error, don't return
one. If it is, filter it back and fail the bind.

> return 0;
> }
>
> @@ -141,19 +170,19 @@ static int lpc_sch_probe(struct pci_dev *dev,
> int ret;
>
> ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus",
> - info->io_size_smbus,
> + info->io_size_smbus, -1,
> id->device, &lpc_sch_cells[cells]);
> if (!ret)
> cells++;
>
> ret = lpc_sch_populate_cell(dev, GPIOBASE, "sch_gpio",
> - info->io_size_gpio,
> + info->io_size_gpio, info->irq_gpio,
> id->device, &lpc_sch_cells[cells]);
> if (!ret)
> cells++;
>
> ret = lpc_sch_populate_cell(dev, WDTBASE, "ie6xx_wdt",
> - info->io_size_wdt,
> + info->io_size_wdt, -1,
> id->device, &lpc_sch_cells[cells]);
> if (!ret)
> cells++;
--
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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