[PATCH v9 01/22] scsi/atari_scsi: Don't select CONFIG_NVRAM

Finn Thain
2019-01-15T04:24:12Z

On powerpc, setting CONFIG_NVRAM=n builds a kernel with no NVRAM support.
Setting CONFIG_NVRAM=m enables the /dev/nvram misc device module without
enabling NVRAM support in drivers. Setting CONFIG_NVRAM=y enables the
misc device (built-in) and also enables NVRAM support in drivers.

m68k shares the valkyriefb driver with powerpc, and since that driver uses
NVRAM, it is affected by CONFIG_ATARI_SCSI, because of the use of
"select NVRAM". We can avoid the "select" here, but drivers still have
to interpret the CONFIG_NVRAM symbol consistently regardless of platform.

In this patch and the subsequent fbdev driver patch, the convention is
adopted across all relevant platforms whereby NVRAM functionality gets
enabled in a given device driver when the nvram misc device is built-in
or when both drivers are modules.

Acked-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
---
This patch temporarily disables CONFIG_NVRAM on Atari, to prevent build
failures when bisecting the rest of this patch series. It gets enabled
again with the introduction of CONFIG_HAVE_ARCH_NVRAM_OPS, once the
nvram_* global functions have been moved to an ops struct.

Changed since v8:
- Replaced defined(CONFIG_NVRAM) with IS_REACHABLE(CONFIG_NVRAM) as
suggested by James Bottomley.
- Changed #ifdef to if as suggested by Christophe Leroy.
---
drivers/char/Kconfig | 5 +----
drivers/scsi/Kconfig | 6 +++---
drivers/scsi/atari_scsi.c | 2 +-
3 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 2e2ffe7010aa..a8cac68de177 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -244,7 +244,7 @@ source "drivers/char/hw_random/Kconfig"

config NVRAM
tristate "/dev/nvram support"
- depends on ATARI || X86 || GENERIC_NVRAM
+ depends on X86 || GENERIC_NVRAM
---help---
If you say Y here and create a character special file /dev/nvram
with major number 10 and minor number 144 using mknod ("man mknod"),
@@ -262,9 +262,6 @@ config NVRAM
should NEVER idly tamper with it. See Ralf Brown's interrupt list
for a guide to the use of CMOS bytes by your BIOS.

- On Atari machines, /dev/nvram is always configured and does not need
- to be selected.
-
To compile this driver as a module, choose M here: the
module will be called nvram.

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index f38882f6f37d..8f9d9e9fa695 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -1369,14 +1369,14 @@ config ATARI_SCSI
tristate "Atari native SCSI support"
depends on ATARI && SCSI
select SCSI_SPI_ATTRS
- select NVRAM
---help---
If you have an Atari with built-in NCR5380 SCSI controller (TT,
Falcon, ...) say Y to get it supported. Of course also, if you have
a compatible SCSI controller (e.g. for Medusa).

- To compile this driver as a module, choose M here: the
- module will be called atari_scsi.
+ To compile this driver as a module, choose M here: the module will
+ be called atari_scsi. If you also enable NVRAM support, the SCSI
+ host's ID is taken from the setting in TT RTC NVRAM.

This driver supports both styles of NCR integration into the
system: the TT style (separate DMA), and the Falcon style (via
diff --git a/drivers/scsi/atari_scsi.c b/drivers/scsi/atari_scsi.c
index a503dc50c4f8..78b43200c99e 100644
--- a/drivers/scsi/atari_scsi.c
+++ b/drivers/scsi/atari_scsi.c
@@ -757,7 +757,7 @@ static int __init atari_scsi_probe(struct platform_device *pdev)

if (setup_hostid >= 0) {
atari_scsi_template.this_id = setup_hostid & 7;
- } else {
+ } else if (IS_REACHABLE(CONFIG_NVRAM)) {
/* Test if a host id is set in the NVRam */
if (ATARIHW_PRESENT(TT_CLK) && nvram_check_checksum()) {
unsigned char b = nvram_read_byte(16);
--
2.19.2