| Message ID | 20220111155709.56501-3-boger@wirenboard.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | add support for Allwinner R40 CAN controller | expand |
On Tue, 11 Jan 2022 18:57:08 +0300 Evgeny Boger <boger@wirenboard.com> wrote: Hi, > Allwinner R40 (also known as A40i, T3, V40) has a CAN controller. The > controller is the same as in earlier A10 and A20 SoCs, but needs reset > line to be deasserted before use. > > This patch adds a new compatible for R40 CAN controller. Depending > on the compatible, reset line can be requested from DT. > > Signed-off-by: Evgeny Boger <boger@wirenboard.com> > --- > drivers/net/can/sun4i_can.c | 61 ++++++++++++++++++++++++++++++++++++- > 1 file changed, 60 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/can/sun4i_can.c b/drivers/net/can/sun4i_can.c > index 54aa7c25c4de..24a61326915e 100644 > --- a/drivers/net/can/sun4i_can.c > +++ b/drivers/net/can/sun4i_can.c > @@ -61,6 +61,7 @@ > #include <linux/of.h> > #include <linux/of_device.h> > #include <linux/platform_device.h> > +#include <linux/reset.h> > > #define DRV_NAME "sun4i_can" > > @@ -200,10 +201,20 @@ > #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 */ > }; > > @@ -702,6 +713,13 @@ static int sun4ican_open(struct net_device *dev) > 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) { > @@ -723,6 +741,8 @@ static int sun4ican_open(struct net_device *dev) > 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); > @@ -736,6 +756,7 @@ static int sun4ican_close(struct net_device *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); > @@ -750,8 +771,27 @@ static const struct net_device_ops sun4ican_netdev_ops = { > .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 > + }, This one looks unnecessary, the binding says that it must be paired with the A10 fallback. We should only add an A20 compatible match if there is really a reason, otherwise it encourages people to produce DTs with *only* the A20 compatible (violating the binding). Cheers, Andre > + { > + .compatible = "allwinner,sun8i-r40-can", > + .data = &sun4ican_quirks_r40 > + }, > {}, > }; > > @@ -771,10 +811,28 @@ static int sun4ican_probe(struct platform_device *pdev) > { > 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)) { > @@ -818,6 +876,7 @@ static int sun4ican_probe(struct platform_device *pdev) > CAN_CTRLMODE_3_SAMPLES; > priv->base = addr; > priv->clk = clk; > + priv->reset = reset; > spin_lock_init(&priv->cmdreg_lock); > > platform_set_drvdata(pdev, dev);
11.01.2022 19:24, Andre Przywara пишет: > On Tue, 11 Jan 2022 18:57:08 +0300 > Evgeny Boger <boger@wirenboard.com> wrote: > > Hi, > >> Allwinner R40 (also known as A40i, T3, V40) has a CAN controller. The >> controller is the same as in earlier A10 and A20 SoCs, but needs reset >> line to be deasserted before use. >> >> This patch adds a new compatible for R40 CAN controller. Depending >> on the compatible, reset line can be requested from DT. >> >> Signed-off-by: Evgeny Boger <boger@wirenboard.com> >> --- >> drivers/net/can/sun4i_can.c | 61 ++++++++++++++++++++++++++++++++++++- >> 1 file changed, 60 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/can/sun4i_can.c b/drivers/net/can/sun4i_can.c >> index 54aa7c25c4de..24a61326915e 100644 >> --- a/drivers/net/can/sun4i_can.c >> +++ b/drivers/net/can/sun4i_can.c >> @@ -61,6 +61,7 @@ >> #include <linux/of.h> >> #include <linux/of_device.h> >> #include <linux/platform_device.h> >> +#include <linux/reset.h> >> >> #define DRV_NAME "sun4i_can" >> >> @@ -200,10 +201,20 @@ >> #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 */ >> }; >> >> @@ -702,6 +713,13 @@ static int sun4ican_open(struct net_device *dev) >> 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) { >> @@ -723,6 +741,8 @@ static int sun4ican_open(struct net_device *dev) >> 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); >> @@ -736,6 +756,7 @@ static int sun4ican_close(struct net_device *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); >> @@ -750,8 +771,27 @@ static const struct net_device_ops sun4ican_netdev_ops = { >> .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 >> + }, > This one looks unnecessary, the binding says that it must be paired with > the A10 fallback. > We should only add an A20 compatible match if there is really a reason, > otherwise it encourages people to produce DTs with *only* the A20 > compatible (violating the binding). Right, thank you! Since this series has been around for a couple of months already, and changes in v2 are trivial, would it make sense to submit v3 right away? > Cheers, > Andre > >> + { >> + .compatible = "allwinner,sun8i-r40-can", >> + .data = &sun4ican_quirks_r40 >> + }, >> {}, >> }; >> >> @@ -771,10 +811,28 @@ static int sun4ican_probe(struct platform_device *pdev) >> { >> 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)) { >> @@ -818,6 +876,7 @@ static int sun4ican_probe(struct platform_device *pdev) >> CAN_CTRLMODE_3_SAMPLES; >> priv->base = addr; >> priv->clk = clk; >> + priv->reset = reset; >> spin_lock_init(&priv->cmdreg_lock); >> >> platform_set_drvdata(pdev, dev);
diff --git a/drivers/net/can/sun4i_can.c b/drivers/net/can/sun4i_can.c index 54aa7c25c4de..24a61326915e 100644 --- a/drivers/net/can/sun4i_can.c +++ b/drivers/net/can/sun4i_can.c @@ -61,6 +61,7 @@ #include <linux/of.h> #include <linux/of_device.h> #include <linux/platform_device.h> +#include <linux/reset.h> #define DRV_NAME "sun4i_can" @@ -200,10 +201,20 @@ #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 */ }; @@ -702,6 +713,13 @@ static int sun4ican_open(struct net_device *dev) 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) { @@ -723,6 +741,8 @@ static int sun4ican_open(struct net_device *dev) 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); @@ -736,6 +756,7 @@ static int sun4ican_close(struct net_device *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); @@ -750,8 +771,27 @@ static const struct net_device_ops sun4ican_netdev_ops = { .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 + }, {}, }; @@ -771,10 +811,28 @@ static int sun4ican_probe(struct platform_device *pdev) { 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)) { @@ -818,6 +876,7 @@ static int sun4ican_probe(struct platform_device *pdev) CAN_CTRLMODE_3_SAMPLES; priv->base = addr; priv->clk = clk; + priv->reset = reset; spin_lock_init(&priv->cmdreg_lock); platform_set_drvdata(pdev, dev);
Allwinner R40 (also known as A40i, T3, V40) has a CAN controller. The controller is the same as in earlier A10 and A20 SoCs, but needs reset line to be deasserted before use. This patch adds a new compatible for R40 CAN controller. Depending on the compatible, reset line can be requested from DT. Signed-off-by: Evgeny Boger <boger@wirenboard.com> --- drivers/net/can/sun4i_can.c | 61 ++++++++++++++++++++++++++++++++++++- 1 file changed, 60 insertions(+), 1 deletion(-)