ARM: OMAP2+: Add function to read GPMC settings from device-tree

 - gpmc,wr-access

 - gpmc,wr-data-mux-bus

GPMC chip-select settings properties for child nodes. All are optional.

- gpmc,burst-length	Page/burst length. Must be 4, 8 or 16.

- gpmc,burst-wrap	Enables wrap bursting

- gpmc,burst-read	Enables read page/burst mode

- gpmc,burst-write	Enables write page/burst mode

- gpmc,device-nand	Device is NAND

- gpmc,device-width	Total width of device(s) connected to a GPMC

			chip-select in bytes. The GPMC supports 8-bit

			and 16-bit devices and so this property must be

			1 or 2.

- gpmc,mux-add-data	Address and data multiplexing configuration.

			Valid values are 1 for address-address-data

			multiplexing mode and 2 for address-data

			multiplexing mode.

- gpmc,sync-read	Enables synchronous read. Defaults to asynchronous

			is this is not set.

- gpmc,sync-write	Enables synchronous writes. Defaults to asynchronous

			is this is not set.

- gpmc,wait-pin		Wait-pin used by client. Must be less than

			"gpmc,num-waitpins".

- gpmc,wait-on-read	Enables wait monitoring on reads.

- gpmc,wait-on-write	Enables wait monitoring on writes.

Example for an AM33xx board:

};

MODULE_DEVICE_TABLE(of, gpmc_dt_ids);

/**

 * gpmc_read_settings_dt - read gpmc settings from device-tree

 * @np:		pointer to device-tree node for a gpmc child device

 * @p:		pointer to gpmc settings structure

 *

 * Reads the GPMC settings for a GPMC child device from device-tree and

 * stores them in the GPMC settings structure passed. The GPMC settings

 * structure is initialised to zero by this function and so any

 * previously stored settings will be cleared.

 */

void gpmc_read_settings_dt(struct device_node *np, struct gpmc_settings *p)

{

	memset(p, 0, sizeof(struct gpmc_settings));

	p->sync_read = of_property_read_bool(np, "gpmc,sync-read");

	p->sync_write = of_property_read_bool(np, "gpmc,sync-write");

	p->device_nand = of_property_read_bool(np, "gpmc,device-nand");

	of_property_read_u32(np, "gpmc,device-width", &p->device_width);

	of_property_read_u32(np, "gpmc,mux-add-data", &p->mux_add_data);

	if (!of_property_read_u32(np, "gpmc,burst-length", &p->burst_len)) {

		p->burst_wrap = of_property_read_bool(np, "gpmc,burst-wrap");

		p->burst_read = of_property_read_bool(np, "gpmc,burst-read");

		p->burst_write = of_property_read_bool(np, "gpmc,burst-write");

		if (!p->burst_read && !p->burst_write)

			pr_warn("%s: page/burst-length set but not used!\n",

				__func__);

	}

	if (!of_property_read_u32(np, "gpmc,wait-pin", &p->wait_pin)) {

		p->wait_on_read = of_property_read_bool(np,

							"gpmc,wait-on-read");

		p->wait_on_write = of_property_read_bool(np,

							 "gpmc,wait-on-write");

		if (!p->wait_on_read && !p->wait_on_write)

			pr_warn("%s: read/write wait monitoring not enabled!\n",

				__func__);

	}

}

static void __maybe_unused gpmc_read_timings_dt(struct device_node *np,

						struct gpmc_timings *gpmc_t)

{

extern void omap3_gpmc_save_context(void);

extern void omap3_gpmc_restore_context(void);

extern int gpmc_configure(int cmd, int wval);

extern void gpmc_read_settings_dt(struct device_node *np,

				  struct gpmc_settings *p);

#endif