Re: [PATCH 19/41] ARM: omap: dma: make usb support optional

Péter Ujfalusi
2022-04-29T19:18:56Z

On 4/19/22 16:37, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> Most of the plat-omap/dma.c code is specific to the USB
> driver.

The reason is simple: the omap_udc is the only driver which has not been
ported to DMAengine.
I had a patch if I recall to convert it, but I don't have a way to test
it and the omap_udc sets some funky bits for DMA which we can not figure
out on how to handle.

> Hide that code when it is not in use, to make it
> clearer which parts are actually still required.

Reviewed-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>

> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> arch/arm/plat-omap/dma.c | 45 +++++++++++++++++-----------------
> drivers/usb/gadget/udc/Kconfig | 2 +-
> include/linux/omap-dma.h | 5 +++-
> 3 files changed, 27 insertions(+), 25 deletions(-)
>
> diff --git a/arch/arm/plat-omap/dma.c b/arch/arm/plat-omap/dma.c
> index 700ba9b600e7..b7757864d0aa 100644
> --- a/arch/arm/plat-omap/dma.c
> +++ b/arch/arm/plat-omap/dma.c
> @@ -66,7 +66,6 @@ enum { DMA_CHAIN_STARTED, DMA_CHAIN_NOTSTARTED };
>
> static struct omap_system_dma_plat_info *p;
> static struct omap_dma_dev_attr *d;
> -static void omap_clear_dma(int lch);
> static int enable_1510_mode;
> static u32 errata;
>
> @@ -90,19 +89,16 @@ static int omap_dma_reserve_channels;
> static DEFINE_SPINLOCK(dma_chan_lock);
> static struct omap_dma_lch *dma_chan;
>
> -static inline void disable_lnk(int lch);
> -static void omap_disable_channel_irq(int lch);
> -static inline void omap_enable_channel_irq(int lch);
> -
> -#ifdef CONFIG_ARCH_OMAP15XX
> -/* Returns 1 if the DMA module is in OMAP1510-compatible mode, 0 otherwise */
> -static int omap_dma_in_1510_mode(void)
> +static inline void omap_disable_channel_irq(int lch)
> {
> - return enable_1510_mode;
> + /* disable channel interrupts */
> + p->dma_write(0, CICR, lch);
> + /* Clear CSR */
> + if (dma_omap1())
> + p->dma_read(CSR, lch);
> + else
> + p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, lch);
> }
> -#else
> -#define omap_dma_in_1510_mode() 0
> -#endif
>
> #ifdef CONFIG_ARCH_OMAP1
> static inline void set_gdma_dev(int req, int dev)
> @@ -169,6 +165,17 @@ void omap_set_dma_priority(int lch, int dst_port, int priority)
> #endif
> EXPORT_SYMBOL(omap_set_dma_priority);
>
> +#if IS_ENABLED(CONFIG_USB_OMAP)
> +#ifdef CONFIG_ARCH_OMAP15XX
> +/* Returns 1 if the DMA module is in OMAP1510-compatible mode, 0 otherwise */
> +static int omap_dma_in_1510_mode(void)
> +{
> + return enable_1510_mode;
> +}
> +#else
> +#define omap_dma_in_1510_mode() 0
> +#endif
> +
> void omap_set_dma_transfer_params(int lch, int data_type, int elem_count,
> int frame_count, int sync_mode,
> int dma_trigger, int src_or_dst_synch)
> @@ -418,17 +425,6 @@ static inline void omap_enable_channel_irq(int lch)
> p->dma_write(dma_chan[lch].enabled_irqs, CICR, lch);
> }
>
> -static inline void omap_disable_channel_irq(int lch)
> -{
> - /* disable channel interrupts */
> - p->dma_write(0, CICR, lch);
> - /* Clear CSR */
> - if (dma_omap1())
> - p->dma_read(CSR, lch);
> - else
> - p->dma_write(OMAP2_DMA_CSR_CLEAR_MASK, CSR, lch);
> -}
> -
> void omap_disable_dma_irq(int lch, u16 bits)
> {
> dma_chan[lch].enabled_irqs &= ~bits;
> @@ -473,6 +469,7 @@ static inline void disable_lnk(int lch)
> p->dma_write(l, CLNK_CTRL, lch);
> dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
> }
> +#endif
>
> int omap_request_dma(int dev_id, const char *dev_name,
> void (*callback)(int lch, u16 ch_status, void *data),
> @@ -572,6 +569,7 @@ static void omap_clear_dma(int lch)
> local_irq_restore(flags);
> }
>
> +#if IS_ENABLED(CONFIG_USB_OMAP)
> void omap_start_dma(int lch)
> {
> u32 l;
> @@ -792,6 +790,7 @@ int omap_get_dma_active_status(int lch)
> return (p->dma_read(CCR, lch) & OMAP_DMA_CCR_EN) != 0;
> }
> EXPORT_SYMBOL(omap_get_dma_active_status);
> +#endif
>
> int omap_dma_running(void)
> {
> diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
> index cee934dce4f0..69394dc1cdfb 100644
> --- a/drivers/usb/gadget/udc/Kconfig
> +++ b/drivers/usb/gadget/udc/Kconfig
> @@ -128,7 +128,7 @@ config USB_GR_UDC
>
> config USB_OMAP
> tristate "OMAP USB Device Controller"
> - depends on ARCH_OMAP1 || (ARCH_OMAP && COMPILE_TEST)
> + depends on ARCH_OMAP1
> depends on ISP1301_OMAP || !(MACH_OMAP_H2 || MACH_OMAP_H3)
> help
> Many Texas Instruments OMAP processors have flexible full
> diff --git a/include/linux/omap-dma.h b/include/linux/omap-dma.h
> index 5e228428fda1..07fa58ae9902 100644
> --- a/include/linux/omap-dma.h
> +++ b/include/linux/omap-dma.h
> @@ -299,8 +299,9 @@ extern void omap_set_dma_priority(int lch, int dst_port, int priority);
> extern int omap_request_dma(int dev_id, const char *dev_name,
> void (*callback)(int lch, u16 ch_status, void *data),
> void *data, int *dma_ch);
> -extern void omap_disable_dma_irq(int ch, u16 irq_bits);
> extern void omap_free_dma(int ch);
> +#if IS_ENABLED(CONFIG_USB_OMAP)
> +extern void omap_disable_dma_irq(int ch, u16 irq_bits);
> extern void omap_start_dma(int lch);
> extern void omap_stop_dma(int lch);
> extern void omap_set_dma_transfer_params(int lch, int data_type,
> @@ -326,6 +327,8 @@ extern void omap_set_dma_dest_burst_mode(int lch,
> extern dma_addr_t omap_get_dma_src_pos(int lch);
> extern dma_addr_t omap_get_dma_dst_pos(int lch);
> extern int omap_get_dma_active_status(int lch);
> +#endif
> +
> extern int omap_dma_running(void);
>
> #if IS_ENABLED(CONFIG_FB_OMAP)

--
Péter