USB: serial: f81534: fix reading old/new IC config

The F81532/534 had a internal configuration space to save & control
IC state with address F81534_CUSTOM_ADDRESS_START (0x2f00). Layout
as following:
	+00h: to indicate the section is valid
	+01h~04h: UART Mode & port availability
	+05h~08h: Output pin control on IC power on
	+09h~12h: Output pin control on working <-- New added

Old driver will use +05~08h as default on working, but newer IC will
configed with shutdown mode(7) in 05h~08h and working mode with RS232(1)
in 09h~12h. It'll make mainstream driver not working.

This patch will make mainstream driver compatible older and newer IC.
If using a old IC, the +05h~08h will be 00h~06h, we'll direct apply it.
If using a new IC, the +05h~08h will be 07h or larger, we'll read +09h~12h
to apply newer configuration.

Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/f81534.c b/drivers/usb/serial/f81534.c
index 380933db34dd500a8414eb1af47c6817208868ed..2b39bda035c71b95f103ad7028c107e77ddfc455 100644 (file)
--- a/drivers/usb/serial/f81534.c
+++ b/drivers/usb/serial/f81534.c
@@ -45,14 +45,17 @@
 #define F81534_CONFIG1_REG             (0x09 + F81534_UART_BASE_ADDRESS)
 
 #define F81534_DEF_CONF_ADDRESS_START  0x3000
-#define F81534_DEF_CONF_SIZE           8
+#define F81534_DEF_CONF_SIZE           12
 
 #define F81534_CUSTOM_ADDRESS_START    0x2f00
 #define F81534_CUSTOM_DATA_SIZE                0x10
 #define F81534_CUSTOM_NO_CUSTOM_DATA   0xff
 #define F81534_CUSTOM_VALID_TOKEN      0xf0
 #define F81534_CONF_OFFSET             1
-#define F81534_CONF_GPIO_OFFSET                4
+#define F81534_CONF_INIT_GPIO_OFFSET   4
+#define F81534_CONF_WORK_GPIO_OFFSET   8
+#define F81534_CONF_GPIO_SHUTDOWN      7
+#define F81534_CONF_GPIO_RS232         1
 
 #define F81534_MAX_DATA_BLOCK          64
 #define F81534_MAX_BUS_RETRY           20
@@ -1337,8 +1340,19 @@ static int f81534_set_port_output_pin(struct usb_serial_port *port)
        serial_priv = usb_get_serial_data(serial);
        port_priv = usb_get_serial_port_data(port);
 
-       idx = F81534_CONF_GPIO_OFFSET + port_priv->phy_num;
+       idx = F81534_CONF_INIT_GPIO_OFFSET + port_priv->phy_num;
        value = serial_priv->conf_data[idx];
+       if (value >= F81534_CONF_GPIO_SHUTDOWN) {
+               /*
+                * Newer IC configure will make transceiver in shutdown mode on
+                * initial power on. We need enable it before using UARTs.
+                */
+               idx = F81534_CONF_WORK_GPIO_OFFSET + port_priv->phy_num;
+               value = serial_priv->conf_data[idx];
+               if (value >= F81534_CONF_GPIO_SHUTDOWN)
+                       value = F81534_CONF_GPIO_RS232;
+       }
+
        pins = &f81534_port_out_pins[port_priv->phy_num];
 
        for (i = 0; i < ARRAY_SIZE(pins->pin); ++i) {