API: provide new line accessors

Add two new public functions that allow to retrieve multiple lines from
GPIO chips at once. Include test cases.

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>

diff --git a/include/gpiod.h b/include/gpiod.h
index eb3f81ceadbe60eb64854a597298acdb5b645ee5..c8ba3e25bd690952ee810ea35aa228bdb1be3ec8 100644 (file)
--- a/include/gpiod.h
+++ b/include/gpiod.h
@@ -47,6 +47,7 @@ struct gpiod_chip;
 struct gpiod_line;
 struct gpiod_chip_iter;
 struct gpiod_line_iter;
+struct gpiod_line_bulk;
 
 /**
  * @defgroup __common__ Common helper macros
@@ -395,6 +396,27 @@ unsigned int gpiod_chip_num_lines(struct gpiod_chip *chip) GPIOD_API;
 struct gpiod_line *
 gpiod_chip_get_line(struct gpiod_chip *chip, unsigned int offset) GPIOD_API;
 
+/**
+ * @brief Retrieve a set of lines and store them in a line bulk object.
+ * @param chip The GPIO chip object.
+ * @param offsets Array of offsets of lines to retrieve.
+ * @param num_offsets Number of lines to retrieve.
+ * @param bulk Line bulk object in which to store the line handles.
+ * @return 0 on success, -1 on error.
+ */
+int gpiod_chip_get_lines(struct gpiod_chip *chip,
+                        unsigned int *offsets, unsigned int num_offsets,
+                        struct gpiod_line_bulk *bulk) GPIOD_API;
+
+/**
+ * @brief Retrieve all lines exposed by a chip and store them in a bulk object.
+ * @param chip The GPIO chip object.
+ * @param bulk Line bulk object in which to store the line handles.
+ * @return 0 on success, -1 on error.
+ */
+int gpiod_chip_get_all_lines(struct gpiod_chip *chip,
+                            struct gpiod_line_bulk *bulk) GPIOD_API;
+
 /**
  * @brief Find a GPIO line by name among lines associated with given GPIO chip.
  * @param chip The GPIO chip object.

diff --git a/src/lib/helpers.c b/src/lib/helpers.c
index 94643faa374c686d7d7b789d3346bec42ef9e390..f479a42036a0b45718cc69d0e53baec2dd18bd3b 100644 (file)
--- a/src/lib/helpers.c
+++ b/src/lib/helpers.c
@@ -103,6 +103,45 @@ struct gpiod_chip *gpiod_chip_open_lookup(const char *descr)
        return chip;
 }
 
+int gpiod_chip_get_lines(struct gpiod_chip *chip, unsigned int *offsets,
+                        unsigned int num_offsets, struct gpiod_line_bulk *bulk)
+{
+       struct gpiod_line *line;
+       unsigned int i;
+
+       gpiod_line_bulk_init(bulk);
+
+       for (i = 0; i < num_offsets; i++) {
+               line = gpiod_chip_get_line(chip, offsets[i]);
+               if (!line)
+                       return -1;
+
+               gpiod_line_bulk_add(bulk, line);
+       }
+
+       return 0;
+}
+
+int gpiod_chip_get_all_lines(struct gpiod_chip *chip,
+                            struct gpiod_line_bulk *bulk)
+{
+       struct gpiod_line_iter *iter;
+       struct gpiod_line *line;
+
+       gpiod_line_bulk_init(bulk);
+
+       iter = gpiod_line_iter_new(chip);
+       if (!iter)
+               return -1;
+
+       gpiod_foreach_line(iter, line)
+               gpiod_line_bulk_add(bulk, line);
+
+       gpiod_line_iter_free(iter);
+
+       return 0;
+}
+
 struct gpiod_line *
 gpiod_chip_find_line(struct gpiod_chip *chip, const char *name)
 {

diff --git a/tests/tests-chip.c b/tests/tests-chip.c
index 3262decc051cd93435be04e02c01705a6a2bdca5..3fa1cbd4092be34512a6855961a8518357f162e1 100644 (file)
--- a/tests/tests-chip.c
+++ b/tests/tests-chip.c
@@ -195,6 +195,66 @@ TEST_DEFINE(chip_num_lines,
            "gpiod_chip_num_lines()",
            0, { 1, 4, 8, 16, 32 });
 
+static void chip_get_lines(void)
+{
+       TEST_CLEANUP(test_close_chip) struct gpiod_chip *chip = NULL;
+       struct gpiod_line_bulk bulk;
+       unsigned int offsets[4];
+       struct gpiod_line *line;
+       int rv;
+
+       chip = gpiod_chip_open(test_chip_path(0));
+       TEST_ASSERT_NOT_NULL(chip);
+
+       offsets[0] = 1;
+       offsets[1] = 3;
+       offsets[2] = 4;
+       offsets[3] = 7;
+
+       rv = gpiod_chip_get_lines(chip, offsets, 4, &bulk);
+       TEST_ASSERT_RET_OK(rv);
+
+       TEST_ASSERT_EQ(gpiod_line_bulk_num_lines(&bulk), 4);
+       line = gpiod_line_bulk_get_line(&bulk, 0);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 1);
+       line = gpiod_line_bulk_get_line(&bulk, 1);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 3);
+       line = gpiod_line_bulk_get_line(&bulk, 2);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 4);
+       line = gpiod_line_bulk_get_line(&bulk, 3);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 7);
+}
+TEST_DEFINE(chip_get_lines,
+           "gpiod_chip_get_lines()",
+           0, { 16 });
+
+static void chip_get_all_lines(void)
+{
+       TEST_CLEANUP(test_close_chip) struct gpiod_chip *chip = NULL;
+       struct gpiod_line_bulk bulk;
+       struct gpiod_line *line;
+       int rv;
+
+       chip = gpiod_chip_open(test_chip_path(0));
+       TEST_ASSERT_NOT_NULL(chip);
+
+       rv = gpiod_chip_get_all_lines(chip, &bulk);
+       TEST_ASSERT_RET_OK(rv);
+
+       TEST_ASSERT_EQ(gpiod_line_bulk_num_lines(&bulk), 4);
+       line = gpiod_line_bulk_get_line(&bulk, 0);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 0);
+       line = gpiod_line_bulk_get_line(&bulk, 1);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 1);
+       line = gpiod_line_bulk_get_line(&bulk, 2);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 2);
+       line = gpiod_line_bulk_get_line(&bulk, 3);
+       TEST_ASSERT_EQ(gpiod_line_offset(line), 3);
+}
+TEST_DEFINE(chip_get_all_lines,
+           "gpiod_chip_get_all_lines()",
+           0, { 4 });
+
 static void chip_find_line_good(void)
 {
        TEST_CLEANUP(test_close_chip) struct gpiod_chip *chip = NULL;