Allow module parameter 'enable_msi' to request an MSI interrupt for
hosts where available (presently PCI). Useful as a workaround on
platforms where the legacy interrupt is broken.
Signed-off-by: Daniel J Blueman <dan...@quora.org>
---
drivers/mmc/host/sdhci-pci.c | 30 ++++++++++++++++++++++++++++++
drivers/mmc/host/sdhci.c | 23 +++++++++++++++++++++++
drivers/mmc/host/sdhci.h | 2 ++
3 files changed, 55 insertions(+)
diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
index 504da71..fbde589 100644
--- a/drivers/mmc/host/sdhci-pci.c
+++ b/drivers/mmc/host/sdhci-pci.c
@@ -934,6 +934,34 @@ static int sdhci_pci_enable_dma(struct sdhci_host *host)
return 0;
}
+static int sdhci_pci_enable_msi(struct sdhci_host *host)
+{
+ struct sdhci_pci_slot *slot;
+ struct pci_dev *pdev;
+ int ret;
+
+ slot = sdhci_priv(host);
+ pdev = slot->chip->pdev;
+
+ ret = pci_enable_msi(pdev);
+ if (ret)
+ return ret;
+
+ host->irq = pdev->irq;
+ return 0;
+}
+
+static void sdhci_pci_disable_msi(struct sdhci_host *host)
+{
+ struct sdhci_pci_slot *slot;
+ struct pci_dev *pdev;
+
+ slot = sdhci_priv(host);
+ pdev = slot->chip->pdev;
+
+ pci_disable_msi(pdev);
+}
+
static int sdhci_pci_8bit_width(struct sdhci_host *host, int width)
{
u8 ctrl;
@@ -976,6 +1004,8 @@ static void sdhci_pci_hw_reset(struct sdhci_host *host)
static struct sdhci_ops sdhci_pci_ops = {
.enable_dma = sdhci_pci_enable_dma,
+ .enable_msi = sdhci_pci_enable_msi,
+ .disable_msi = sdhci_pci_disable_msi,
.platform_8bit_width = sdhci_pci_8bit_width,
.hw_reset = sdhci_pci_hw_reset,
};
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 9a11dc3..9fa2180 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -45,6 +45,7 @@
static unsigned int debug_quirks = 0;
static unsigned int debug_quirks2;
+static bool enable_msi;
static void sdhci_finish_data(struct sdhci_host *);
@@ -2433,6 +2434,9 @@ int sdhci_suspend_host(struct sdhci_host *host)
free_irq(host->irq, host);
+ if (host->ops->disable_msi && enable_msi)
+ host->ops->disable_msi(host);
+
return ret;
}
@@ -2447,6 +2451,12 @@ int sdhci_resume_host(struct sdhci_host *host)
host->ops->enable_dma(host);
}
+ if (host->ops->enable_msi && enable_msi) {
+ ret = host->ops->enable_msi(host);
+ if (ret)
+ return ret;
+ }
+
ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
mmc_hostname(host->mmc), host);
if (ret)
@@ -3024,6 +3034,12 @@ int sdhci_add_host(struct sdhci_host *host)
host->tuning_timer.function = sdhci_tuning_timer;
}
+ if (host->ops->enable_msi && enable_msi) {
+ ret = host->ops->enable_msi(host);
+ if (ret)
+ return ret;
+ }
+
ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
mmc_hostname(mmc), host);
if (ret) {
@@ -3071,6 +3087,8 @@ int sdhci_add_host(struct sdhci_host *host)
reset:
sdhci_reset(host, SDHCI_RESET_ALL);
free_irq(host->irq, host);
+ if (host->ops->disable_msi && enable_msi)
+ host->ops->disable_msi(host);
#endif
untasklet:
tasklet_kill(&host->card_tasklet);
@@ -3114,6 +3132,9 @@ void sdhci_remove_host(struct sdhci_host *host, int dead)
free_irq(host->irq, host);
+ if (host->ops->disable_msi && enable_msi)
+ host->ops->disable_msi(host);
+
del_timer_sync(&host->timer);
tasklet_kill(&host->card_tasklet);
@@ -3162,6 +3183,7 @@ module_exit(sdhci_drv_exit);
module_param(debug_quirks, uint, 0444);
module_param(debug_quirks2, uint, 0444);
+module_param(enable_msi, bool, 0444);
MODULE_AUTHOR("Pierre Ossman <pie...@ossman.eu>");
MODULE_DESCRIPTION("Secure Digital Host Controller Interface core driver");
@@ -3169,3 +3191,4 @@ MODULE_LICENSE("GPL");
MODULE_PARM_DESC(debug_quirks, "Force certain quirks.");
MODULE_PARM_DESC(debug_quirks2, "Force certain other quirks.");
+MODULE_PARM_DESC(debug_quirks2, "Enable MSI interrupt support where
possible.");
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 97653ea..df4e003 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -264,6 +264,8 @@ struct sdhci_ops {
void (*set_clock)(struct sdhci_host *host, unsigned int clock);
int (*enable_dma)(struct sdhci_host *host);
+ int (*enable_msi)(struct sdhci_host *host);
+ void (*disable_msi)(struct sdhci_host *host);
unsigned int (*get_max_clock)(struct sdhci_host *host);
unsigned int (*get_min_clock)(struct sdhci_host *host);
unsigned int (*get_timeout_clock)(struct sdhci_host *host);
--
1.7.10.4
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