summaryrefslogtreecommitdiffstats
path: root/drivers/media/pci/mantis/mantis_uart.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/media/pci/mantis/mantis_uart.c')
-rw-r--r--drivers/media/pci/mantis/mantis_uart.c186
1 files changed, 186 insertions, 0 deletions
diff --git a/drivers/media/pci/mantis/mantis_uart.c b/drivers/media/pci/mantis/mantis_uart.c
new file mode 100644
index 000000000..42983a89e
--- /dev/null
+++ b/drivers/media/pci/mantis/mantis_uart.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ Mantis PCI bridge driver
+
+ Copyright (C) Manu Abraham (abraham.manu@gmail.com)
+
+*/
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <asm/io.h>
+
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+
+#include <media/dmxdev.h>
+#include <media/dvbdev.h>
+#include <media/dvb_demux.h>
+#include <media/dvb_frontend.h>
+#include <media/dvb_net.h>
+
+#include "mantis_common.h"
+#include "mantis_reg.h"
+#include "mantis_uart.h"
+#include "mantis_input.h"
+
+struct mantis_uart_params {
+ enum mantis_baud baud_rate;
+ enum mantis_parity parity;
+};
+
+static struct {
+ char string[7];
+} rates[5] = {
+ { "9600" },
+ { "19200" },
+ { "38400" },
+ { "57600" },
+ { "115200" }
+};
+
+static struct {
+ char string[5];
+} parity[3] = {
+ { "NONE" },
+ { "ODD" },
+ { "EVEN" }
+};
+
+static void mantis_uart_read(struct mantis_pci *mantis)
+{
+ struct mantis_hwconfig *config = mantis->hwconfig;
+ int i, scancode = 0, err = 0;
+
+ /* get data */
+ dprintk(MANTIS_DEBUG, 1, "UART Reading ...");
+ for (i = 0; i < (config->bytes + 1); i++) {
+ int data = mmread(MANTIS_UART_RXD);
+
+ dprintk(MANTIS_DEBUG, 0, " <%02x>", data);
+
+ scancode = (scancode << 8) | (data & 0x3f);
+ err |= data;
+
+ if (data & (1 << 7))
+ dprintk(MANTIS_ERROR, 1, "UART framing error");
+
+ if (data & (1 << 6))
+ dprintk(MANTIS_ERROR, 1, "UART parity error");
+ }
+ dprintk(MANTIS_DEBUG, 0, "\n");
+
+ if ((err & 0xC0) == 0)
+ mantis_input_process(mantis, scancode);
+}
+
+static void mantis_uart_work(struct work_struct *work)
+{
+ struct mantis_pci *mantis = container_of(work, struct mantis_pci, uart_work);
+ u32 stat;
+ unsigned long timeout;
+
+ stat = mmread(MANTIS_UART_STAT);
+
+ if (stat & MANTIS_UART_RXFIFO_FULL)
+ dprintk(MANTIS_ERROR, 1, "RX Fifo FULL");
+
+ /*
+ * MANTIS_UART_RXFIFO_DATA is only set if at least
+ * config->bytes + 1 bytes are in the FIFO.
+ */
+
+ /* FIXME: is 10ms good enough ? */
+ timeout = jiffies + msecs_to_jiffies(10);
+ while (stat & MANTIS_UART_RXFIFO_DATA) {
+ mantis_uart_read(mantis);
+ stat = mmread(MANTIS_UART_STAT);
+
+ if (!time_is_after_jiffies(timeout))
+ break;
+ }
+
+ /* re-enable UART (RX) interrupt */
+ mantis_unmask_ints(mantis, MANTIS_INT_IRQ1);
+}
+
+static int mantis_uart_setup(struct mantis_pci *mantis,
+ struct mantis_uart_params *params)
+{
+ u32 reg;
+
+ mmwrite((mmread(MANTIS_UART_CTL) | (params->parity & 0x3)), MANTIS_UART_CTL);
+
+ reg = mmread(MANTIS_UART_BAUD);
+
+ switch (params->baud_rate) {
+ case MANTIS_BAUD_9600:
+ reg |= 0xd8;
+ break;
+ case MANTIS_BAUD_19200:
+ reg |= 0x6c;
+ break;
+ case MANTIS_BAUD_38400:
+ reg |= 0x36;
+ break;
+ case MANTIS_BAUD_57600:
+ reg |= 0x23;
+ break;
+ case MANTIS_BAUD_115200:
+ reg |= 0x11;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ mmwrite(reg, MANTIS_UART_BAUD);
+
+ return 0;
+}
+
+int mantis_uart_init(struct mantis_pci *mantis)
+{
+ struct mantis_hwconfig *config = mantis->hwconfig;
+ struct mantis_uart_params params;
+
+ /* default parity: */
+ params.baud_rate = config->baud_rate;
+ params.parity = config->parity;
+ dprintk(MANTIS_INFO, 1, "Initializing UART @ %sbps parity:%s",
+ rates[params.baud_rate].string,
+ parity[params.parity].string);
+
+ INIT_WORK(&mantis->uart_work, mantis_uart_work);
+
+ /* disable interrupt */
+ mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
+
+ mantis_uart_setup(mantis, &params);
+
+ /* default 1 byte */
+ mmwrite((mmread(MANTIS_UART_BAUD) | (config->bytes << 8)), MANTIS_UART_BAUD);
+
+ /* flush buffer */
+ mmwrite((mmread(MANTIS_UART_CTL) | MANTIS_UART_RXFLUSH), MANTIS_UART_CTL);
+
+ /* enable interrupt */
+ mmwrite(mmread(MANTIS_UART_CTL) | MANTIS_UART_RXINT, MANTIS_UART_CTL);
+ mantis_unmask_ints(mantis, MANTIS_INT_IRQ1);
+
+ schedule_work(&mantis->uart_work);
+ dprintk(MANTIS_DEBUG, 1, "UART successfully initialized");
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mantis_uart_init);
+
+void mantis_uart_exit(struct mantis_pci *mantis)
+{
+ /* disable interrupt */
+ mantis_mask_ints(mantis, MANTIS_INT_IRQ1);
+ mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
+ flush_work(&mantis->uart_work);
+}
+EXPORT_SYMBOL_GPL(mantis_uart_exit);