[PATCH V6 3/3] mmc: sdhci: Add MSI interrupt support for O2 SD host

From: ernest.zhang
Date: Tue Jun 26 2018 - 11:47:38 EST


Add MSI interrupt support if the SD host device can support MSI interrupt.

Signed-off-by: ernest.zhang <ernest.zhang@xxxxxxxxxxxxxx>
---
Changes in V6:
1. Move change log to correct place.
2. Reduce unneeded pr_info prints.
3. In function sdhci_pci_o2_probe_slot, remove using local
variable 'mmc' instead of using 'host->mmc'.
3. Make the msi enable code a sperate function.

Changes in V5:
1. Because pci_enable_msi is marked as deprecated and should not be
used in new code, use pci_alloc_irq_vectors instead.
2. Remove unneeded CONFIG_PCI_MSI macro check.

Changes in V4:
Enable MSI interrupt if the MSI capability bit is set in
capability register.
---
drivers/mmc/host/sdhci-pci-o2micro.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c
index 7747e8b..56bc717 100644
--- a/drivers/mmc/host/sdhci-pci-o2micro.c
+++ b/drivers/mmc/host/sdhci-pci-o2micro.c
@@ -260,6 +260,29 @@ static void sdhci_pci_o2_fujin2_pci_init(struct sdhci_pci_chip *chip)
pci_write_config_dword(chip->pdev, O2_SD_MISC_CTRL4, scratch_32);
}

+static void sdhci_pci_o2_enable_msi(struct sdhci_pci_chip *chip,
+ struct sdhci_host *host)
+{
+ int ret;
+
+ ret = pci_find_capability(chip->pdev, PCI_CAP_ID_MSI);
+ if (!ret) {
+ pr_info("%s: unsupport msi, use INTx irq\n",
+ mmc_hostname(host->mmc));
+ return;
+ }
+
+ ret = pci_alloc_irq_vectors(chip->pdev, 1, 1,
+ PCI_IRQ_MSI | PCI_IRQ_MSIX);
+ if (ret < 0) {
+ pr_err("%s: enable PCI MSI failed, err=%d\n",
+ mmc_hostname(host->mmc), ret);
+ return;
+ }
+
+ host->irq = pci_irq_vector(chip->pdev, 0);
+}
+
int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
{
struct sdhci_pci_chip *chip;
@@ -279,6 +302,8 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
if (reg & 0x1)
host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;

+ sdhci_pci_o2_enable_msi(chip, host);
+
if (chip->pdev->device == PCI_DEVICE_ID_O2_SEABIRD0) {
ret = pci_read_config_dword(chip->pdev,
O2_SD_MISC_SETTING, &reg);
--
2.7.4