tdm/test: Added loopback test module for tdm

This module requires tdm device to be configure in loopback mode.
This test will write sample data on a tdm channel and compare
the read value with the sample data sent.

Signed-off-by: Sandeep Singh <Sandeep@freescale.com>
Change-Id: I2db7d40c0177c0b5e3a54467dab90c4de9d9b975
Reviewed-on: http://git.am.freescale.net:8181/7001
Tested-by: Review Code-CDREVIEW <CDREVIEW@freescale.com>
Reviewed-by: Poonam Aggrwal <Poonam.Aggrwal@freescale.com>
Reviewed-by: Jose Rivera <German.Rivera@freescale.com>

3 files changed, 259 insertions, 0 deletions

diff --git a/drivers/tdm/test/Kconfig b/drivers/tdm/test/Kconfig
index 81fc3f4..39f9581 100644
--- a/drivers/tdm/test/Kconfig
+++ b/drivers/tdm/test/Kconfig
@@ -19,4 +19,11 @@ config UCC_TDM_TEST
 	  This UCC TDM test module is a small test module to test
 	  ucc tdm transfer and receive data via ucc1.
 
+config TDM_LOOPBACK_TEST
+        tristate "TDM Loopback test Module"
+	depends on FSL_SOC
+	---help---
+	  This TDM Loopback test module is a small test module which
+	  performs a simple internal loopback testing.
+
 endmenu
diff --git a/drivers/tdm/test/Makefile b/drivers/tdm/test/Makefile
index c229934..47bb4ef 100644
--- a/drivers/tdm/test/Makefile
+++ b/drivers/tdm/test/Makefile
@@ -4,3 +4,4 @@
 
 obj-$(CONFIG_TDM_TEST)  += tdm_test.o
 obj-$(CONFIG_UCC_TDM_TEST)	+= ucc_tdm_test.o
+obj-$(CONFIG_TDM_LOOPBACK_TEST)  += tdm_loopback_test.o
diff --git a/drivers/tdm/test/tdm_loopback_test.c b/drivers/tdm/test/tdm_loopback_test.c
new file mode 100644
index 0000000..49554aa
--- /dev/null
+++ b/drivers/tdm/test/tdm_loopback_test.c
@@ -0,0 +1,251 @@
+/*
+ *
+ * Copyright 2011-2012 Freescale Semiconductor, Inc.
+ *
+ * TDM Loopback Test Module.
+ * This TDM test module is a small test module which registers with the
+ * TDM framework and transfer and receive data in loopback mode and also
+ * compares if the data sent is received correctly.
+ *
+ * Author: Sandeep Kumar Singh <sandeep@freescale.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the  GNU General Public License along
+ * with this program; if not, write  to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
+#include <linux/param.h>
+#include <linux/tdm.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/tdm.h>
+
+
+#define DRV_DESC "Test Module for Freescale Platforms with TDM support"
+#define DRV_NAME "tdm_test"
+
+
+#define POLL_COUNT 		38
+#define TDM_FRAME_LENGTH	NUM_SAMPLES_PER_FRAME
+#define TDM_E_OK		0
+#define BUF_COUNT		7
+
+#define DEBUG 0
+
+int poll_count = POLL_COUNT;
+module_param(poll_count, int, 0);
+
+static struct task_struct *tdm_thread_task;
+static struct tdm_driver test_tdmdev_driver;
+struct tdm_port *tdmport;
+int tdm_thread_state;
+
+static int tdm_check_data(unsigned short *tx_data, unsigned short *rx_data)
+{
+	int i, error = 0;
+	static int call_count;
+
+	for (i = 1; i < TDM_FRAME_LENGTH; i++) {
+		if (tx_data[i] != rx_data[i])
+			error++;
+		else
+			continue;
+	}
+
+	pr_info("Iteration: %d\n", ++call_count);
+#if DEBUG
+	pr_info("TX DATA:\n");
+	for (i = 0; i < TDM_FRAME_LENGTH; i++) {
+		pr_info("%5x ", tx_data[i]);
+		if (i%20 == 19)
+			pr_info("\n");
+	}
+	pr_info("RX DATA:\n");
+	for (i = 0; i < TDM_FRAME_LENGTH; i++) {
+		pr_info("%5x ", rx_data[i]);
+		if (i%20 == 19)
+			pr_info("\n");
+	}
+#endif
+	if (error)
+		pr_info("TX and RX buffer do NOT match. Err_count:"
+				"%d\n", error);
+	else
+		pr_info("TX and RX buffer MATCH\n");
+
+	return error;
+}
+
+
+static int tdm_thread(void *ptr)
+{
+	void *h_port;
+	void *h_channel1;
+	int ret = TDM_E_OK;
+	int poll = 0;
+	int i = 0, j = 0;
+	int index = 0;
+	int error_count = 0;
+	int buffer_size;
+	uint16_t size = TDM_FRAME_LENGTH;
+	u16 ch1_id = 0;
+	unsigned short *tx_data[BUF_COUNT];
+	unsigned short *rx_data[BUF_COUNT];
+
+	tdm_thread_state = 1;
+
+	/* Open port */
+	ret = tdm_port_open(&test_tdmdev_driver, &h_port);
+	pr_debug("%s tdm_port_open ret = %d\n", __func__, ret);
+	if ((ret != TDM_E_OK) || (h_port == NULL)) {
+		pr_err("Error in tdm_port_open- ret %x\n", ret);
+		goto port1_failed;
+	}
+	/* Open Channel 1*/
+	ret = tdm_channel_open(ch1_id, 1, h_port, &h_channel1);
+	if ((ret != TDM_E_OK) || (h_channel1 == NULL)) {
+		pr_err("Error in tdm_channel_open(%d)- ret %x\n", ch1_id, ret);
+		goto ch1_failed;
+	}
+
+	buffer_size = sizeof(unsigned short)*BUF_COUNT*TDM_FRAME_LENGTH;
+	tx_data[0] = kmalloc(buffer_size, GFP_KERNEL);
+	rx_data[0] = kmalloc(buffer_size, GFP_KERNEL);
+
+	if ((tx_data[0] == NULL) || (rx_data[0] == NULL)) {
+		pr_err("Failed to get memory for buffer");
+		return 0;
+	}
+	for (i = 0; i < BUF_COUNT-1; i++) {
+		tx_data[i+1] = tx_data[i] + TDM_FRAME_LENGTH;
+		rx_data[i+1] = rx_data[i] + TDM_FRAME_LENGTH;
+	}
+	while ((poll < poll_count) && !kthread_should_stop()) {
+
+		poll++;
+		while (tdm_ch_poll(h_channel1, 10) != TDM_E_OK)
+			continue;
+		for (i = 0; i < TDM_FRAME_LENGTH; i++)
+			tx_data[index][i] = j*TDM_FRAME_LENGTH+i;
+
+		ret = tdm_channel_write(h_port, h_channel1, tx_data[index],
+					size);
+		if (ret != TDM_E_OK)
+			pr_info("Error in tdm_channel_write\n");
+		ret = tdm_channel_read(h_port, h_channel1, rx_data[index],
+					&size);
+		if (ret != TDM_E_OK)
+			pr_info("Error in tdm_channel_read\n");
+		/*
+		 * There is a delay of 6 frame  between transmitted data and
+		 * received data. Hence we compare tx_data[0] with rx data[6]
+		 * and so on
+		 */
+		if (j++ > BUF_COUNT)
+			error_count += tdm_check_data(tx_data[(index + 1)
+					%BUF_COUNT], rx_data[index]);
+		index++;
+		index = index%BUF_COUNT;
+
+	}
+	pr_info("\nTDM Loppback test completed.\n");
+	if (error_count == 0)
+		pr_info("TDM loopback test PASSED!\n");
+	else
+		pr_info("TDM loopback test FAILED!\n");
+
+	ret = tdm_channel_close(ch1_id, 1, h_port, h_channel1);
+	if (ret != TDM_E_OK) {
+		pr_err("Error in tdm_channel_close(%d)- ret %x\n", ch1_id, ret);
+		ret = -ENXIO;
+	}
+
+	ret = tdm_port_close(h_port);
+	pr_debug("%s tdm_port_close ret = %d\n", __func__, ret);
+	if (ret != TDM_E_OK) {
+		pr_err("Error in tdm_port_close- ret %x\n", ret);
+		ret = -ENXIO;
+	}
+
+	tdm_thread_state = 0;
+
+	return ret;
+
+ch1_failed:
+	tdm_channel_close(ch1_id, 1, h_port, h_channel1);
+port1_failed:
+	tdm_port_close(h_port);
+	return -ENXIO;
+}
+
+static int test_attach_adapter(struct tdm_adapter *adap)
+{
+	tdm_thread_state = 0;
+	tdm_thread_task = kthread_run(tdm_thread, NULL, "tdm_thread");
+
+	return 0;
+}
+
+static int test_detach_adapter(struct tdm_adapter *adap)
+{
+	if (tdm_thread_state)
+		kthread_stop(tdm_thread_task);
+
+	return 0;
+}
+
+static const struct tdm_device_id tdm_loopback_test_id[] = {
+	{ "fsl_tdm", 0 },
+	{ }
+};
+
+static struct tdm_driver test_tdmdev_driver = {
+	.attach_adapter	= test_attach_adapter,
+	.detach_adapter	= test_detach_adapter,
+	.id_table	= tdm_loopback_test_id,
+};
+
+static int __init tdm_loopback_test_init(void)
+{
+	int ret;
+	pr_info("TDM LOOPBACK TEST: \n");
+	test_tdmdev_driver.id = 1;
+
+	/* create a binding with TDM driver */
+	ret = tdm_add_driver(&test_tdmdev_driver);
+	if (ret == 0)
+		pr_info("TDM LOOPBACK TEST module installed\n");
+	else
+		pr_err("%s tdm_port_init failed\n", __func__);
+	return ret;
+}
+
+static void __exit tdm_loopback_test_exit(void)
+{
+	tdm_unregister_driver(&test_tdmdev_driver);
+	pr_info("TDM LOOPBACK TEST module un-installed\n");
+}
+
+module_init(tdm_loopback_test_init);
+module_exit(tdm_loopback_test_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sandeep Kumar Singh <sandeep@freescale.com>");
+MODULE_DESCRIPTION("Test Loopback Test Module for Freescale Platforms"
+" with TDM support");