#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/reset.h>
#define DRV_NAME "sun4i_can"
#define SUN4I_CAN_MAX_IRQ 20
#define SUN4I_MODE_MAX_RETRIES 100
+/**
+ * struct sun4ican_quirks - Differences between SoC variants.
+ *
+ * @has_reset: SoC needs reset deasserted.
+ */
+struct sun4ican_quirks {
+ bool has_reset;
+};
+
struct sun4ican_priv {
struct can_priv can;
void __iomem *base;
struct clk *clk;
+ struct reset_control *reset;
spinlock_t cmdreg_lock; /* lock for concurrent cmd register writes */
};
goto exit_irq;
}
+ /* software reset deassert */
+ err = reset_control_deassert(priv->reset);
+ if (err) {
+ netdev_err(dev, "could not deassert CAN reset\n");
+ goto exit_soft_reset;
+ }
+
/* turn on clocking for CAN peripheral block */
err = clk_prepare_enable(priv->clk);
if (err) {
exit_can_start:
clk_disable_unprepare(priv->clk);
exit_clock:
+ reset_control_assert(priv->reset);
+exit_soft_reset:
free_irq(dev->irq, dev);
exit_irq:
close_candev(dev);
netif_stop_queue(dev);
sun4i_can_stop(dev);
clk_disable_unprepare(priv->clk);
+ reset_control_assert(priv->reset);
free_irq(dev->irq, dev);
close_candev(dev);
.ndo_start_xmit = sun4ican_start_xmit,
};
+static const struct sun4ican_quirks sun4ican_quirks_a10 = {
+ .has_reset = false,
+};
+
+static const struct sun4ican_quirks sun4ican_quirks_r40 = {
+ .has_reset = true,
+};
+
static const struct of_device_id sun4ican_of_match[] = {
- {.compatible = "allwinner,sun4i-a10-can"},
- {},
+ {
+ .compatible = "allwinner,sun4i-a10-can",
+ .data = &sun4ican_quirks_a10
+ }, {
+ .compatible = "allwinner,sun7i-a20-can",
+ .data = &sun4ican_quirks_a10
+ }, {
+ .compatible = "allwinner,sun8i-r40-can",
+ .data = &sun4ican_quirks_r40
+ }, {
+ /* sentinel */
+ },
};
MODULE_DEVICE_TABLE(of, sun4ican_of_match);
{
struct device_node *np = pdev->dev.of_node;
struct clk *clk;
+ struct reset_control *reset = NULL;
void __iomem *addr;
int err, irq;
struct net_device *dev;
struct sun4ican_priv *priv;
+ const struct sun4ican_quirks *quirks;
+
+ quirks = of_device_get_match_data(&pdev->dev);
+ if (!quirks) {
+ dev_err(&pdev->dev, "failed to determine the quirks to use\n");
+ err = -ENODEV;
+ goto exit;
+ }
+
+ if (quirks->has_reset) {
+ reset = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+ if (IS_ERR(reset)) {
+ dev_err(&pdev->dev, "unable to request reset\n");
+ err = PTR_ERR(reset);
+ goto exit;
+ }
+ }
clk = of_clk_get(np, 0);
if (IS_ERR(clk)) {
CAN_CTRLMODE_3_SAMPLES;
priv->base = addr;
priv->clk = clk;
+ priv->reset = reset;
spin_lock_init(&priv->cmdreg_lock);
platform_set_drvdata(pdev, dev);