spi: Convert CONFIG_DM_SPI* to CONFIG_$(SPL_TPL_)DM_SPI*

This change allows more fine tuning of driver model based SPI support in
SPL and TPL. It is now possible to explicitly enable/disable the DM_SPI
support in SPL and TPL via Kconfig option.

Before this change it was necessary to use:
    /* SPI Flash Configs */
    #if defined(CONFIG_SPL_BUILD)
    #undef CONFIG_DM_SPI
    #undef CONFIG_DM_SPI_FLASH
    #undef CONFIG_SPI_FLASH_MTD
    #endif

in the ./include/configs/<board>.h, which is error prone and shall be
avoided when we strive to switch to Kconfig.

The goal of this patch:

Provide distinction for DM_SPI support in both U-Boot proper and SPL (TPL).
Valid use case is when U-Boot proper wants to use DM_SPI, but SPL must
still support non DM driver.

Another use case is the conversion of non DM/DTS SPI driver to support
DM/DTS. When such driver needs to work in both SPL and U-Boot proper, the
distinction is needed in Kconfig (also if SPL version of the driver
supports OF_PLATDATA).

In the end of the day one would have to support following use cases (in
single driver file - e.g. mxs_spi.c):

- U-Boot proper driver supporting DT/DTS
- U-Boot proper driver without DT/DTS support (deprecated)
- SPL driver without DT/DTS support
- SPL (and TPL) driver with DT/DTS (when the SoC has enough resources to
  run full blown DT/DTS)
- SPL driver with DT/DTS and SPL_OF_PLATDATA (when one have constrained
  environment with no fitImage and OF_LIBFDT support).

Some boards do require SPI support (with DM) in SPL (TPL) and some only
have DM_SPI{_FLASH} defined to allow compiling SPL.

This patch converts #ifdef CONFIG_DM_SPI* to #if CONFIG_IS_ENABLED(DM_SPI)
and provides corresponding defines in Kconfig.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Tested-by: Adam Ford <aford173@gmail.com> #da850-evm
Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
[trini: Fixup a few platforms]
Signed-off-by: Tom Rini <trini@konsulko.com>

cmd/sf.c

@@ -91,7 +91,7 @@ static int do_spi_flash_probe(int argc, char *const argv[])
 	unsigned int speed = CONFIG_SF_DEFAULT_SPEED;
 	unsigned int mode = CONFIG_SF_DEFAULT_MODE;
 	char *endp;
-#ifdef CONFIG_DM_SPI_FLASH
+#if CONFIG_IS_ENABLED(DM_SPI_FLASH)
 	struct udevice *new, *bus_dev;
 	int ret;
 #else
@@ -124,7 +124,7 @@ static int do_spi_flash_probe(int argc, char *const argv[])
 			return -1;
 	}
 
-#ifdef CONFIG_DM_SPI_FLASH
+#if CONFIG_IS_ENABLED(DM_SPI_FLASH)
 	/* Remove the old device, otherwise probe will just be a nop */
 	ret = spi_find_bus_and_cs(bus, cs, &bus_dev, &new);
 	if (!ret) {

cmd/spi.c

@@ -38,7 +38,7 @@ static int do_spi_xfer(int bus, int cs)
 	struct spi_slave *slave;
 	int ret = 0;
 
-#ifdef CONFIG_DM_SPI
+#if CONFIG_IS_ENABLED(DM_SPI)
 	char name[30], *str;
 	struct udevice *dev;
 
@@ -63,7 +63,7 @@ static int do_spi_xfer(int bus, int cs)
 		goto done;
 	ret = spi_xfer(slave, bitlen, dout, din,
 		       SPI_XFER_BEGIN | SPI_XFER_END);
-#ifndef CONFIG_DM_SPI
+#if !CONFIG_IS_ENABLED(DM_SPI)
 	/* We don't get an error code in this case */
 	if (ret)
 		ret = -EIO;
@@ -79,7 +79,7 @@ static int do_spi_xfer(int bus, int cs)
 	}
 done:
 	spi_release_bus(slave);
-#ifndef CONFIG_DM_SPI
+#if !CONFIG_IS_ENABLED(DM_SPI)
 	spi_free_slave(slave);
 #endif