[PATCH 4.9 004/141] pcmcia: Implement CLKRUN protocol disabling for Ricoh bridges

Greg Kroah-Hartman
2018-11-11T22:47:00Z

From: Maciej S. Szmigiero <mail@maciej.szmigiero.name>

commit 95691e3eddc41da2d1cd3cca51fecdfb46bd85bc upstream.

Currently, "disable_clkrun" yenta_socket module parameter is only
implemented for TI CardBus bridges.
Add also an implementation for Ricoh bridges that have the necessary
setting documented in publicly available datasheets.

Tested on a RL5C476II with a Sunrich C-160 CardBus NIC that doesn't work
correctly unless the CLKRUN protocol is disabled.

Let's also make it clear in its description that the "disable_clkrun"
module parameter only works on these two previously mentioned brands of
CardBus bridges.

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Cc: stable@vger.kernel.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/pcmcia/ricoh.h | 35 +++++++++++++++++++++++++++++++++++
drivers/pcmcia/yenta_socket.c | 3 ++-
2 files changed, 37 insertions(+), 1 deletion(-)

--- a/drivers/pcmcia/ricoh.h
+++ b/drivers/pcmcia/ricoh.h
@@ -119,6 +119,10 @@
#define RL5C4XX_MISC_CONTROL 0x2F /* 8 bit */
#define RL5C4XX_ZV_ENABLE 0x08

+/* Misc Control 3 Register */
+#define RL5C4XX_MISC3 0x00A2 /* 16 bit */
+#define RL5C47X_MISC3_CB_CLKRUN_DIS BIT(1)
+
#ifdef __YENTA_H

#define rl_misc(socket) ((socket)->private[0])
@@ -156,6 +160,35 @@ static void ricoh_set_zv(struct yenta_so
}
}

+static void ricoh_set_clkrun(struct yenta_socket *socket, bool quiet)
+{
+ u16 misc3;
+
+ /*
+ * RL5C475II likely has this setting, too, however no datasheet
+ * is publicly available for this chip
+ */
+ if (socket->dev->device != PCI_DEVICE_ID_RICOH_RL5C476 &&
+ socket->dev->device != PCI_DEVICE_ID_RICOH_RL5C478)
+ return;
+
+ if (socket->dev->revision < 0x80)
+ return;
+
+ misc3 = config_readw(socket, RL5C4XX_MISC3);
+ if (misc3 & RL5C47X_MISC3_CB_CLKRUN_DIS) {
+ if (!quiet)
+ dev_dbg(&socket->dev->dev,
+ "CLKRUN feature already disabled\n");
+ } else if (disable_clkrun) {
+ if (!quiet)
+ dev_info(&socket->dev->dev,
+ "Disabling CLKRUN feature\n");
+ misc3 |= RL5C47X_MISC3_CB_CLKRUN_DIS;
+ config_writew(socket, RL5C4XX_MISC3, misc3);
+ }
+}
+
static void ricoh_save_state(struct yenta_socket *socket)
{
rl_misc(socket) = config_readw(socket, RL5C4XX_MISC);
@@ -172,6 +205,7 @@ static void ricoh_restore_state(struct y
config_writew(socket, RL5C4XX_16BIT_IO_0, rl_io(socket));
config_writew(socket, RL5C4XX_16BIT_MEM_0, rl_mem(socket));
config_writew(socket, RL5C4XX_CONFIG, rl_config(socket));
+ ricoh_set_clkrun(socket, true);
}

@@ -197,6 +231,7 @@ static int ricoh_override(struct yenta_s
config_writew(socket, RL5C4XX_CONFIG, config);

ricoh_set_zv(socket);
+ ricoh_set_clkrun(socket, false);

return 0;
}
--- a/drivers/pcmcia/yenta_socket.c
+++ b/drivers/pcmcia/yenta_socket.c
@@ -26,7 +26,8 @@

static bool disable_clkrun;
module_param(disable_clkrun, bool, 0444);
-MODULE_PARM_DESC(disable_clkrun, "If PC card doesn't function properly, please try this option");
+MODULE_PARM_DESC(disable_clkrun,
+ "If PC card doesn't function properly, please try this option (TI and Ricoh bridges only)");

static bool isa_probe = 1;
module_param(isa_probe, bool, 0444);